The correct answer is: a) High temperatures and scorching sun.
Summer months in Tamil Nadu (March-May) are characterized by high temperatures and scorching sun. The average temperature during these months ranges from 30 to 40 degrees Celsius. The sun is very strong during these months and it is important to take precautions against sunstroke.
Option b) is incorrect because the temperatures during summer months in Tamil Nadu are not moderate. They are very high.
Option c) is incorrect because the weather during summer months in Tamil Nadu is not pleasant. It is very hot and humid.
Option d) is incorrect because the temperatures during summer months in Tamil Nadu are not cold. They are very hot.