Answer:

The correct answer is option 'C', Shimla.

Shimla, also known as Simla, is a famous hill station located in the state of Himachal Pradesh in northern India. It was the summer capital of British India during the colonial era and served as a retreat from the scorching heat of the plains. One of the key reasons for its selection as the summer capital was its pleasant climate and picturesque surroundings.

Role of Viceroy John Lawrence:
In 1864, the Viceroy of India, John Lawrence, made the decision to officially move his council to Shimla. This meant that the administrative headquarters of British India shifted to this hill station during the summer months. The decision was made to escape the extreme heat of the Indian plains and to ensure a more comfortable and conducive environment for conducting government affairs.

Residence of the Commander-in-Chief:
In addition to being the summer capital, Shimla also became the official residence of the Commander-in-Chief of the Indian Army. The Commander-in-Chief was the highest-ranking military officer in British India and having the headquarters in Shimla allowed for better coordination and administration of the armed forces.

Reasons for Choosing Shimla:
There were several reasons why Shimla was chosen as the preferred hill station for the Viceroy and the Commander-in-Chief:

1. Climate: Shimla's climate is mild and pleasant throughout the year, making it an ideal location for the summer capital. The temperature remains cool even during the peak summer months, providing respite from the scorching heat of the plains.

2. Strategic Location: Shimla is strategically located in the foothills of the Himalayas, providing a natural barrier against any potential invasions from the north. This made it a suitable location for the Commander-in-Chief to oversee the defense of the Indian subcontinent.

3. Accessibility: Shimla's location in the northern part of India made it easily accessible from major cities like Delhi and Kolkata. The construction of the Kalka-Shimla Railway line further improved connectivity, making it convenient for officials and British residents to travel to and from Shimla.

4. Natural Beauty: Shimla is surrounded by lush green hills, beautiful valleys, and picturesque landscapes. Its natural beauty and serene environment made it an ideal retreat for the British officials and their families.

In conclusion, Shimla became the official summer capital and the residence of the Commander-in-Chief of the Indian Army in 1864, under the leadership of Viceroy John Lawrence. Its pleasant climate, strategic location, accessibility, and natural beauty made it a perfect choice for conducting government affairs and military operations during the summer months.