In the Later Vedic economy, what was the primary ecological and technological limitation that prevented the immediate, widespread use of heavy iron ploughshares in the middle Gangetic plains (including Bihar) during the early phase?

Options:

• A: Complete lack of iron ore deposits in the Indian subcontinent prior to the 6th century BCE.
• B: The waterlogged, alluvial soil of the middle Gangetic valley required drainage rather than deep-ploughing, making heavy iron ploughs redundant.
• C: The early iron technology was soft and brittle (wrought iron), making it ineffective for clearing the dense, deep-rooted monsoon forests of Bihar without copper alloying.
• D: Iron was initially a scarce, high-status metal reserved primarily for weaponry and elite prestige goods, rather than mass-produced agricultural tools.

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