Directions: Read the Assertion (A) and Reason (R) carefully and choose the correct alternative. Assertion (A): Tamil Nadu receives most of its annual rainfall during the winter months. Reason (R): Tamil Nadu gets significant rainfall from the retreating or northeast monsoon winds.

Introduction / Context:
This Assertion and Reason question relates to the climate of Tamil Nadu and the Indian monsoon system. Most parts of India receive the bulk of their rainfall from the southwest monsoon in the summer months. However, Tamil Nadu is a well known exception, receiving a large share of its rainfall during the later part of the year. Understanding this helps strengthen concepts in Indian climatology and regional rainfall patterns.

Given Data / Assumptions:

• Assertion (A): Tamil Nadu gets most of its rainfall in winter.
• Reason (R): Tamil Nadu gets rainfall from retreating monsoons.
• Retreating monsoon refers to the period when the southwest monsoon withdraws and winds change direction, bringing the northeast monsoon.
• We focus on the months roughly from October to December as winter rainfall season for Tamil Nadu.

Concept / Approach:
During June to September, the southwest monsoon brings heavy rain to most parts of India, but it gives relatively less rain to the eastern coast of Tamil Nadu because this region is in the rain shadow of the Western Ghats for that wind direction. Later in the year, when the monsoon retreats and winds reverse to blow from the northeast, these winds pick up moisture from the Bay of Bengal and give rain to the Tamil Nadu coast. This northeast or retreating monsoon season becomes the main rainy period for the state.

Step-by-Step Solution:
Step 1: Examine Assertion (A). Climate data for Tamil Nadu show that a large proportion of annual rainfall occurs during the months of October, November, and early December. Step 2: Compared to many other Indian states, which receive maximum rainfall in the southwest monsoon, Tamil Nadu receives a major share during these later, cooler months. So Assertion (A) is true. Step 3: Reason (R) mentions rainfall from retreating monsoons, also known as the northeast monsoon. After the withdrawal of the southwest monsoon, winds reverse direction and blow from land to sea, from the northeast towards the Bay of Bengal. Step 4: As these northeast monsoon winds pass over the Bay of Bengal, they pick up moisture and then strike the eastern coast of India, especially Tamil Nadu and nearby regions. Step 5: This leads to heavy and sometimes cyclonic rainfall over Tamil Nadu during the retreating monsoon period. Therefore Reason (R) is true. Step 6: The rainfall from the retreating monsoon is precisely the cause of Tamil Nadu receiving most of its rainfall in the winter months, so Reason (R) correctly explains Assertion (A).

Verification / Alternative check:
Geography textbooks explicitly highlight Tamil Nadu as a state that receives heavy rainfall during the retreating monsoon and treat it as a textbook example of winter rainfall in India. They also show rainfall distribution graphs that peak in October and November for cities like Chennai. These confirm that both the Assertion and the Reason are accurate and properly linked.

Why Other Options Are Wrong:
Options suggesting that Assertion (A) is false ignore well known rainfall statistics for Tamil Nadu. Options claiming the Reason is false misrepresent the northeast monsoon, which is central to rainfall in the region. Saying both are true but R does not explain A is incorrect because the retreating monsoon is exactly why winter rainfall dominates in Tamil Nadu.

Common Pitfalls:
Some students generalise the southwest monsoon pattern for all of India and do not remember regional exceptions like Tamil Nadu and parts of Andhra Pradesh. Others may confuse winter rainfall in Tamil Nadu with western disturbances that affect northwestern India in winter. It is important to keep these mechanisms distinct.

Final Answer:
Both Assertion (A) and Reason (R) are true, and Reason (R) correctly explains Assertion (A), so the correct option is Both Assertion (A) and Reason (R) are true, and Reason (R) correctly explains Assertion (A).