The correct option is (a).
Explanation
The Harappan Civilization (Indus Valley Civilization) represents the first phase of urbanization in South Asia. It is distinguished from earlier Neolithic farming communities by its advanced civic planning, technological advancements in metallurgy, and complex economic structures.
Statement-wise Analysis
- Statement 1 is Correct: The Harappan civilization belongs to the Bronze Age. While Neolithic cultures primarily relied on polished stone tools, the Harappans extensively used copper and bronze (an alloy of copper and tin) to manufacture tools, weapons, ornaments, and vessels.
- Statement 2 is Correct: Harappan cities possessed a distinct system of writing. This script is found on thousands of seals, pottery shards, and copper tablets. Although the script remains undeciphered (boustrophedon style), its existence marks a transition from pre-historic to proto-historic society.
- Statement 3 is Incorrect: One of the most remarkable features of Harappan urbanization was its sophisticated drainage system. Almost every house was connected to street drains, which were covered with bricks or stone slabs and equipped with manholes for regular cleaning. This level of sanitation was absent in Neolithic villages.
- Statement 4 is Incorrect: Harappan trade was facilitated by a highly standardized system of weights and measures. Weights were usually made of chert (a type of stone), were cubical in shape, and devoid of markings. The lower denominations followed a binary system (1, 2, 4, 8, 16, 32, etc.), while higher denominations followed the decimal system.
Key Takeaway: The Indus Valley Civilization is characterized by standardization and urban planning-specifically through its underground drainage systems, uniform brick sizes, and regulated weights-which fundamentally differentiates it from the unorganized, rural nature of Neolithic settlements.