Archaeologists commonly name ancient cultures after the site where they were first identified or studied. The Harappan Civilization derives its name from Harappa, one of the earliest discovered sites. Option D correctly reflects this convention. Options A, B, and C are incorrect because archaeological naming is not necessarily based on deities, scripts, or nearby rivers.

The term "Indus Valley Civilisation" is geographically restrictive because Harappan settlements and artefacts have been discovered far beyond the Indus basin, including Gujarat, Maharashtra, Haryana, Rajasthan, and Afghanistan. Thus, the Assertion is true. The Reason accurately explains why the term is inadequate. Therefore, both statements are true, and the Reason correctly explains the Assertion.

Kalibangan provides evidence of a ploughed field. Terracotta plough models were found in Cholistan and Banawali. Traces of canals have been identified at Shortughai, while Dholavira is famous for its extensive water reservoirs. These associations produce the sequence 1-c, 2-a, 3-b, and 4-d. Hence Option B is correct.

Harappans consumed diverse plant and animal foods, including fish. Archaeo-botanists reconstruct diet from charred grains and seeds. Domesticated animals included cattle, sheep, goat, and buffalo. Rice has been found at some sites but was relatively rare compared to wheat and barley. Therefore, Option C is the incorrect statement and the correct answer.

The passage clearly states that after 1900 BCE, characteristic Harappan artefacts such as weights, seals, and special beads disappeared. Writing, long-distance trade, and craft specialization also declined. Therefore Option C directly reflects the transformation described. The remaining options contradict the passage and are unsupported by archaeological evidence.

The passage explicitly states that artefacts and settlements of the Late Harappan or successor cultures indicate a rural way of life. Distinctive urban features such as writing, long-distance trade, and craft specialization declined. Therefore, Option D correctly reflects the evidence. The remaining options contradict the passage and archaeological findings.

During the nineteenth century, large quantities of baked bricks from Harappa were removed and reused for constructing the railway line between Lahore and Multan. This caused significant damage to the archaeological site. Option A is therefore correct. The other cities were not part of the railway project mentioned in the historical account.

After the partition of India in 1947, major Harappan sites such as Harappa and Mohenjodaro became part of Pakistan. This encouraged Indian archaeologists to search for Harappan settlements within India. Thus, both the Assertion and Reason are true, and the Reason correctly explains the Assertion. Therefore, Option B is the correct answer.

Archaeological evidence indicates that the Mature Harappan phase developed gradually from earlier regional cultures. In several areas, Mature Harappan settlements emerged where Early Harappan communities already existed. Similarities in subsistence strategies and cultural practices demonstrate continuity. Therefore, Option B is correct. The other options exaggerate discontinuity and contradict archaeological findings.

Option A is incorrect because canals have not been definitively identified in Punjab in a manner proving exclusive river-based irrigation. Harappans likely used multiple water-management methods, including wells, reservoirs, and seasonal flooding. Options B, C, and D are supported by archaeological evidence regarding seals, Kalibangan's ploughed field, and charred grain remains.

Alexander Cunningham was the first Director-General of the Archaeological Survey of India. John Marshall announced the discovery of the Harappan Civilization in 1924. R.E.M. Wheeler emphasized stratigraphic excavation with military precision. Vasant Shinde initiated archaeogenetic research at Rakhigarhi. Therefore the correct matching is 1-c, 2-a, 3-b, 4-d, making Option C correct.

The construction of huge mud-brick platforms beneath buildings in both the Citadel and Lower Town required moving enormous quantities of earth and bricks. Such work demanded large-scale labour mobilization and planning. Therefore both the Assertion and Reason are true, and the Reason correctly explains why urban construction required substantial labour. Hence Option D is correct.

Alexander Cunningham reported the Harappan seal in the nineteenth century. Daya Ram Sahni began excavations at Harappa in 1921. Excavations at Mohenjodaro started shortly afterward in 1922. Therefore the chronological sequence is Cunningham's report, Harappa excavations, and then Mohenjodaro excavations. Hence Option C is correct.

Rakhigarhi, located in Haryana, is regarded as the largest known Harappan city. Archaeologists extracted DNA from human skeletal remains found there to investigate Harappan genetic history. Kalibangan, Banawali, and Mitathal are important archaeological sites but were not the source of the landmark DNA study. Therefore, Option B is correct.

One of the most distinctive features of Mohenjodaro was its carefully planned drainage system. Roads and streets followed an approximate grid pattern and intersected at right angles. Drains were laid out before houses were constructed. This demonstrates advanced urban planning. Therefore, Option D is correct, while the remaining options contradict archaeological evidence.

Water reservoirs discovered at Dholavira demonstrate advanced water management. Both Dholavira and Lothal had fortified settlements. A large signboard bearing Harappan script symbols was also found at Dholavira. Option A is incorrect because at Lothal, houses were generally built of mud bricks, while drains were constructed using burnt bricks. Therefore, Option A is the correct answer.

Chanhudaro is known as a specialized manufacturing settlement within the Harappan Civilization. Archaeological evidence shows extensive craft activities such as bead-making, shell working, and metal-working. Because the settlement was largely devoted to production rather than administration or trade, the Reason directly explains the Assertion. Therefore Option A is correct.

Chemical analysis has revealed traces of nickel in both Omani copper and Harappan copper artefacts. This suggests that copper or copper-bearing materials moved through trade networks connecting Oman and the Harappan world. No deciphered Harappan texts have been found in Oman, and iron tools were not characteristic of the Harappan period. Hence Option C is correct.

According to NCERT chronology, Harappan cultural development began during the Early Harappan phase around 6000 BCE and continued through the Mature and Late Harappan phases until approximately 1300 BCE. Therefore Option D correctly represents the broad chronological span of the civilization. The remaining dates represent only specific phases rather than the entire sequence.

Archaeological stratigraphy is based on the principle that lower layers were deposited earlier and are therefore generally older than layers above them. The statement reverses this principle by claiming that lower layers are more recent. Hence the statement is completely false. Therefore Option B is correct, while the other options contradict basic archaeological methodology.