Assertion–Reason (North Indian rivers flood in summer) Assertion (A): Most rivers in the North Indian plains experience flooding during the summer season. Reason (R1): Many rivers originate in the Himalayas and are fed by melting snow. Reason (R2): The rivers are also fed by monsoon rains during the summer months. Identify which reason(s) truly explain A.

Introduction / Context:Flood seasonality in North Indian plains reflects dual inputs: Himalayan snowmelt and monsoon rainfall. The item asks if both reasons explain observed summer flooding.

Given Data / Assumptions:

• A: Summer flooding is common.
• R1: Snowmelt augments discharge from Himalayan catchments.
• R2: Monsoon rains peak in summer, further increasing flows.

Concept / Approach:Hydrographs in snow–monsoon regimes show combined contributions. When both inputs overlap temporally, peak flows and flood probability rise.

Step-by-Step Solution:

Verification / Alternative check:Historical flood records align with monsoon onset and elevated melt periods.

Why Other Options Are Wrong:A/B understate the dual-driver nature; D contradicts hydrology.

Common Pitfalls:Treating snowmelt and monsoon as mutually exclusive.

Final Answer:If both (R1) and (R2) are reasons for the assertion (A).