The period after the 1962 war witnessed:

Increased development efforts in Arunachal Pradesh
Heightened militarization of the region
Greater focus on border security
All of the above

The correct answer is: d) All of the above.

After the 1962 Sino-Indian War, India increased its development efforts in Arunachal Pradesh, heightened the militarization of the region, and focused more on border security.

The war was a major setback for India, and the government realized that it needed to do more to protect its northern border. One way to do this was to develop Arunachal Pradesh, which was then a sparsely populated and underdeveloped region. The government built roads, schools, and hospitals in the state, and it also encouraged people to move there.

The government also heightened the militarization of the region. It built new military bases and increased the number of troops stationed in Arunachal Pradesh. This was done to deter China from attacking again.

Finally, the government focused more on border security. It built new fences and roads along the border, and it increased the number of border guards. This was done to prevent infiltration from China.

The 1962 war had a profound impact on India’s relationship with China. It also led to a number of changes in India’s policy towards Arunachal Pradesh. The government’s development efforts, heightened militarization, and focus on border security were all designed to protect India’s northern border and deter China from attacking again.