The correct answer is (b), Bangladesh. India shares a border of 4,096 kilometers with Bangladesh, making it the country with which India shares its maximum border. The other options are incorrect because they do not share as much border with India as Bangladesh does. China shares a border of 3,488 kilometers with India, Nepal shares a border of 1,751 kilometers with India, and Pakistan shares a border of 3,323 kilometers with India.
India and Bangladesh share a long and complex history. The two countries were once part of the same country, British India, but they were partitioned in 1947 along religious lines. The partition led to violence and displacement, and the two countries have had a tense relationship ever since. However, in recent years, there have been efforts to improve relations between India and Bangladesh. The two countries have signed a number of agreements, and they have increased trade and investment.