Q&A: practice questions with answers

Concept: The Harappan (Indus Valley) civilisation is the earliest known example of planned urbanism in South Asia.

1. Cities like Mohenjo-daro, Harappa and Kalibangan had streets cutting each other at right angles in a grid (chessboard) pattern, with covered drains, baked-brick houses and a separate citadel.
2. Houses were of standardised baked bricks, not wood or stone palaces; irregular streets are a feature of later early-medieval towns, not Harappan cities.

Yaad rakhein: Harappan hallmarks: grid plan, drainage, Great Bath, standard bricks $(1:2:4)$, seals, no temples or palaces found.

Answer: (C) Grid system of town planning

Concept: Articles 23 and 24 form the Right against Exploitation.

1. Article 23 prohibits traffic in human beings, begar and other forms of forced labour; violation is punishable by law.
2. Child employment in hazardous industries (below 14 years) is prohibited by Article 24, not 23.
3. Compulsory service for public purposes is actually permitted under Article 23(2); abolition of titles is Article 18.

Yaad rakhein: 23 = Trafficking & forced labour, 24 = Child labour.

Answer: (C) Trafficking in human beings

Concept: Forest types in India are classified mainly by rainfall; the leaf-shedding habit distinguishes evergreen from deciduous forests.

1. Tropical evergreen forests occur in areas with more than 200 cm rainfall (Western Ghats, NE India, Andaman & Nicobar).
2. Trees here have no definite time to shed leaves, so the forest looks green all year.
3. Deciduous forests shed leaves for 6–8 weeks in dry summer; thorn forests have scrub vegetation.

Yaad rakhein: Ever-green = green for ever, no fixed leaf-fall season.

Answer: (C) Tropical evergreen forests

Concept: GlowCas9 is a glowing (bioluminescent) version of the CRISPR Cas9 protein that lets scientists see where gene editing is happening.

1. In December 2025, scientists of Bose Institute, Kolkata (an autonomous institute under DST) reported creating GlowCas9.
2. The light emitted by the protein lets researchers track Cas9 activity inside cells without killing them.

Yaad rakhein: GlowCas9 → Bose Institute, Kolkata (Dec 2025).

Answer: (D) Bose Institute, Kolkata

Concept: The 69th Constitutional Amendment Act, 1991 inserted Articles 239AA and 239AB, giving Delhi special status as the National Capital Territory.

1. To implement it, Parliament passed the Government of National Capital Territory of Delhi Act, 1991, which created a 70-member Legislative Assembly and a Council of Ministers for Delhi.
2. The Delhi Administration Act, 1966 had earlier set up only a Metropolitan Council; "Delhi Governance Act, 2001" and "Delhi Administration Act, 1987" are not real Acts.

Yaad rakhein: 69th Amendment + GNCTD Act = 1991; first Delhi Assembly election = 1993.

Answer: (D) Government of NCT of Delhi Act, 1991

Concept: The main characteristics of a computer are speed, accuracy, diligence, versatility, storage, reliability and consistency.

1. Consistency (also called reliability/diligence) means the computer gives exactly the same output every time for the same input and instructions, without fatigue or mood.
2. Flexibility/versatility is the ability to do many different kinds of tasks; mobility and expansion are not standard characteristics.

Yaad rakhein: Same input + same program = same output, always → Consistency.

Answer: (B) Consistency

Concept: "Sivam Subham" joins the names of T. Sadasivam and M.S. Subbulakshmi.

1. The biography traces the life of Carnatic legend M.S. Subbulakshmi (Bharat Ratna, 1998) and her husband, freelance journalist and film producer T. Sadasivam.
2. It was in the news in October 2025, which marks Subbulakshmi's birth anniversary month (16 September 1916) and its release coverage.

Yaad rakhein: Siva(m) from Sadasivam + Subha(m) from Subbulakshmi.

Answer: (B) M.S. Subbulakshmi and T. Sadasivam

Concept: The Extremist phase (1905–1919) of the national movement was led by the trio Lal-Bal-Pal.

1. Lala Lajpat Rai of Punjab was called "Punjab Kesari" or the Lion of Punjab; he died in 1928 after lathi blows during the anti-Simon Commission protest.
2. Bal Gangadhar Tilak was "Lokmanya"; Bhagat Singh and Rajguru belong to the later revolutionary phase.

Yaad rakhein: Lal (Punjab) – Bal (Maharashtra) – Pal (Bengal).

Answer: (C) Lala Lajpat Rai

Concept: World Wetlands Day is observed every year on 2 February, the date of adoption of the Ramsar Convention on Wetlands (2 February 1971, Ramsar, Iran).

1. In 2026 it was observed on 2 February with the theme "Wetlands and traditional knowledge: Celebrating cultural heritage".
2. The date never changes, so options for 1, 3 or 4 February are wrong.

Yaad rakhein: 2 Feb – Wetlands; 1 Feb – Indian Coast Guard Day; 4 Feb – World Cancer Day.

Answer: (D) February 2

Concept: A gene can exist in alternative forms that occupy the same position (locus) on homologous chromosomes.

1. These alternative forms are called alleles, e.g. the tall (T) and dwarf (t) alleles of the height gene in pea plants.
2. Genotype is the allele combination (TT, Tt, tt) an organism carries, phenotype is the visible trait, and chromosomes are the structures that carry genes.

Yaad rakhein: Allele = Alternative form of a gene (both start with "Al").

Answer: (D) Alleles

Concept: The Padma Vibhushan is India's second-highest civilian award, given for exceptional and distinguished service.

1. Kathak maestro Pandit Birju Maharaj (Lucknow gharana) received the Padma Vibhushan in 1986 for his contribution to Indian classical dance.
2. Mallika Sarabhai and Shovana Narayan are Padma Bhushan awardees; Birju Maharaj is the best-known Padma Vibhushan recipient among the choices.

Yaad rakhein: Birju Maharaj – Kathak – Padma Vibhushan 1986.

Answer: (C) Birju Maharaj

Concept: The Karakoram range holds the largest glaciers outside the polar regions.

1. Siachen Glacier (about 76 km) is the longest glacier in the Karakoram and the second longest in the world outside the poles, after Fedchenko (Tajikistan).
2. Baltoro is also in the Karakoram but shorter (about 63 km); Gangotri and Pindari are Himalayan glaciers in Uttarakhand.

Yaad rakhein: Siachen = world's highest battlefield and longest Karakoram glacier.

Answer: (C) Siachen Glacier

Concept: Speed is the characteristic that describes how fast a computer processes instructions, measured in microseconds, nanoseconds or even picoseconds.

1. Performing millions of calculations in a fraction of a second is a direct example of speed.
2. Accuracy refers to error-free results, storage to holding data, and versatility to doing varied tasks; none describes "how fast".

Yaad rakhein: "Millions per second" → Speed; "no mistakes" → Accuracy; "many kinds of work" → Versatility.

Answer: (D) Speed

Concept: The Ashtadiggajas were the eight great Telugu poets in the court of Krishnadevaraya of Vijayanagara.

1. Madayagari Mallana, one of the Ashtadiggajas, wrote Rajashekharacharitra, a Prabandha on the wars and loves of Rajashekhara, king of Avanti.
2. Allasani Peddana wrote Manucharitra; Krishnadevaraya himself wrote Amuktamalyada; Nachana Somanatha (earlier period) wrote Uttara Harivamsam.

Yaad rakhein: Mallana – Rajashekharacharitra; Peddana – Manucharitra; Raya – Amuktamalyada.

Answer: (B) Madayagari Mallana

Concept: Leading zeros are never significant; trailing zeros after a decimal point are significant.

1. In 0.00200 the zeros before 2 only fix the decimal place → not counted.
2. The digits 2, 0, 0 after it are significant → 3 significant figures.
3. In scientific notation $0.00200=2.00\times {10}^{-3}$, which shows the 3 figures clearly.

Trick: Write the number in scientific notation; the digits in the mantissa are the significant figures.

Answer: (C) 3

Concept: The Gurjara-Pratihara dynasty (8th–11th century) acted as a barrier against Arab expansion from Sindh into India.

1. Nagabhata I (c. 730–760 CE), the founder, defeated the Arab forces of the Sindh governor Junaid and is praised in the Gwalior inscription as the destroyer of the mleccha army.
2. Mihira Bhoja was the greatest ruler of the dynasty but later (836–885); Ramabhadra was a weak ruler; Yasovarman was a Kannauj king, not a Pratihara.

Yaad rakhein: Nagabhata I = Arab resistance; Mihira Bhoja = Adivaraha, Kannauj glory.

Answer: (B) Nagabhata I

Concept: Alt + F4 is the Windows shortcut to close the active window or application; on the desktop it opens the Shut Down dialog.

1. Switching tabs is Ctrl + Tab, the Find dialog is Ctrl + F, and deleting selected text is the Delete key.
2. Ctrl + F4 closes only the current document/tab inside an application, while Alt + F4 closes the whole program.

Yaad rakhein: Alt + F4 = Application band (close); Ctrl + F4 = tab/document band.

Answer: (C) Close the current window or application

Concept: Time is directly proportional to the number of pages when the speed is constant.

1. Time for 1 page $=\frac{40}{2}=20$ minutes.
2. Time for 84 pages $=84\times 20=1680$ minutes.

Trick: Find the rate per unit first ($20$ min/page), then multiply – no need for cross-multiplication.

Answer: (C) 1680

Concept: By the remainder theorem, the remainder on dividing $f(x)$ by $(x-k)$ is $f(k)$.

1. Let $f(x)=x^2+bx+c$ (leading coefficient 1). Given $f(2)=5$ and $f(4)=-3$.
2. $4+2b+c=5\Rightarrow 2b+c=1$; $16+4b+c=-3\Rightarrow 4b+c=-19$.
3. Subtracting: $2b=-20\Rightarrow b=-10$, so $c=21$.
4. $f(x)=x^2-10x+21$, i.e. $x^2-10x+21=0$.

Trick: Faster: test the options – only option (A) gives $f(2)=4-20+21=5$ and $f(4)=16-40+21=-3$.

Answer: (A) $x^2-10x+21=0$

Concept: Margin of victory = (winner% − loser%) of the valid votes.

1. Let registered voters $=N$. Votes polled $=80\%$ of $N=0.8N$.
2. Valid votes $=97\%$ of $0.8N=0.776N$.
3. Winner $52\%$, loser $48\%$ → margin $=4\%$ of valid votes $=0.04\times 0.776N=0.03104N$.
4. $0.03104N=291\Rightarrow N=\frac{291}{0.03104}=9375$.

Trick: Chain the percentages: $N\times \frac{80}{100}\times \frac{97}{100}\times \frac{4}{100}=291$; $291=3\times 97$ cancels neatly with 97.

Answer: (D) 9375