INDIA — Watershed and river origins in the Peninsula. Most major peninsular rivers in India draw their main watershed and headwaters from which physiographic feature?

Introduction / Context:
The Peninsular plateau of India has a distinct drainage pattern compared to the Indo-Gangetic Plain. Understanding where the principal watersheds lie clarifies river flow directions, monsoon rainfall capture, and hydropower locations.

Given Data / Assumptions:

• We focus on peninsular rivers such as Godavari, Krishna, Kaveri, and many west-flowing short streams.
• “Main watershed” refers to the high-relief divide where rivers originate.
• We distinguish among several Indian hill systems.

Concept / Approach:
The Western Ghats (Sahyadris) form a long, high escarpment parallel to India’s west coast. They act as a major water divide: many short, swift rivers flow west to the Arabian Sea, while longer rivers like Godavari, Krishna, and Kaveri rise near the Ghats and flow east across the Deccan to the Bay of Bengal. Other hill ranges listed do not serve as the principal peninsular watershed.

Step-by-Step Solution:
Identify the feature aligned N–S along the west coast → Western Ghats.Relate to river origins: numerous headwaters arise here due to orographic rainfall.Exclude Aravalli (NW India), Rajmahal (NE near Jharkhand), Siwalik (outer Himalaya, northern India), and Vindhyan escarpments (central but not the main peninsular divide).

Verification / Alternative check:
Hydrographic maps show dense drainage on both flanks of the Western Ghats, confirming their role as the key watershed for peninsular rivers.

Why Other Options Are Wrong:
Aravalli — ancient range in Rajasthan; limited perennial drainage.Rajmahal — localized hills; not the peninsula-wide divide.Siwalik — Himalayan foreland hills, unrelated to peninsular headwaters.Vindhyan Escarpment — significant but not the principal watershed for most peninsular rivers.

Common Pitfalls:
Confusing the cultural north–south boundary (Vindhyas) with the hydrological divide of the peninsula. For drainage, the Western Ghats dominate.

Final Answer:
Western Ghats