The correct choice is Option 3: October - November.

Detailed Explanation:

The Season of Retreating Monsoon (also known as the Transition Season or North-East Monsoon onset) occurs during the months of October and November.

Why does it occur?

During October and November, the apparent movement of the sun shifts southwards. As a result, the low-pressure trough over the northern plains becomes weaker and is gradually replaced by a high-pressure system.

Consequently, the southwest monsoon winds begin to weaken and steadily withdraw from the northern plains of India by the beginning of October. This process is known as the Retreat of the Monsoon.

Key Characteristics of this Season:

Clear Skies and Rise in Temperature: The retreat is marked by clear skies and an increase in daily temperatures. While days are quite hot, nights remain cool and pleasant.

October Heat: Because of the combination of high temperatures and high humidity left behind by the rains, the weather becomes oppressive during the day. This phenomenon is commonly referred to as 'October Heat'.

Cyclones on the Eastern Coast: The low-pressure conditions shift down to the Bay of Bengal by early November. This shift triggers the origination of fierce tropical cyclones that heavily strike the eastern coast of India (especially the deltas of the Godavari, Krishna, and Kaveri rivers), causing widespread rainfall and damage in states like Andhra Pradesh and Tamil Nadu.