Option 1 is correct because both the assertion and the reason are true, and the reason correctly explains the assertion. The statement "West-flowing rivers of Peninsular India have no deltas" is true because deltas form when a river carries sediment, or alluvium, which deposits at the mouth of the river causing the river to split and spread out, forming a delta. But the reason, "These rivers do not carry any alluvial sediments," explains why there are no deltas. Without sediment, there`s nothing to form a delta.

In option 2, the assertion and reason are true, but the reason doesn`t explain the assertion, while option 3, has a true assertion but a false reason. Option 4 depicts a scenario where the assertion is false but the reason is true. However, in this case, both the assertion and the reason are correct, and the reason accurately explains the assertion.