The correct answer is: Summer.
Manali and Shimla are popular tourist destinations during the summer because of their pleasant weather and beautiful scenery. The average temperature in Manali during the summer is around 20 degrees Celsius, while the average temperature in Shimla is around 25 degrees Celsius. Both cities are located in the foothills of the Himalayas, and they offer stunning views of the mountains. In addition, Manali is known for its temples and monasteries, while Shimla is known for its colonial architecture.
The monsoon season in India runs from June to September. During this time, the weather is hot and humid, and there is a lot of rain. This can make it difficult to travel and enjoy the outdoors.
The winter season in India runs from December to February. During this time, the weather is cold and dry. This can make it difficult to enjoy the outdoors, as many of the tourist attractions are closed.
The spring season in India runs from March to May. During this time, the weather is warm and pleasant. This is a good time to visit Manali and Shimla, as the weather is ideal for outdoor activities.