CLIMATE OF INDIA — Southern Deccan rain shadow (units standardized) The southern Deccan Plateau lies in the rain shadow of the Western Ghats. It typically receives about how much rainfall per year (express your choice in mm; note 50–100 cm = 500–1,000 mm)?

Introduction / Context:
The Western Ghats force moist monsoon winds to rise, causing heavy rain on the windward (west) side. Air descending the leeward (east) side is drier, creating a rain-shadow zone across parts of interior Karnataka, Tamil Nadu plateau, Telangana margins, and adjoining Deccan areas.

Given Data / Assumptions:

• Question targets a broad average for the southern Deccan interior.
• Units are standardized: 1 cm = 10 mm; 50–100 cm equals 500–1,000 mm.
• Local variations exist, but we seek a representative range.

Concept / Approach:
Orographic rainfall peaks on the windward slopes (>2,000 mm). In the rain shadow, annual totals are markedly lower, commonly around 500–1,000 mm. This average captures interior districts that are drier than the Konkan–Malabar coast but wetter than semi-arid Rajasthan–Kachchh.

Step-by-Step Solution:
Recognize orographic effect of Western Ghats producing rain shadow to the east.Recall typical isohyets in the southern Deccan interior → ~500–1,000 mm.Select the option with standardized units matching 50–100 cm.

Verification / Alternative check:
Climatological atlases show interior Karnataka–Rayalaseema belts with ~600–900 mm on average, increasing toward coastal belts and decreasing in specific lee pockets.

Why Other Options Are Wrong:
100–200 mm / 200–400 mm / 50–400 mm — too low for the general interior average; these ranges describe semi-arid to arid pockets, not the broader southern Deccan.1,200–2,000 mm — characteristic of windward/coastal zones, not the leeward interior.

Common Pitfalls:
Confusing highly wet Ghats/coastal zones with the drier interior; always account for orographic shadowing.

Final Answer:
500 to 1,000 mm of rainfall a year (≈ 50–100 cm)