Why did Bismillah Khan come to Banaras in childhood?

Correct answer: To learn shehnai from his maternal uncle

Bismillah Khan came to Banaras during childhood to learn the shehnai from his maternal uncle, Ali Bux. This relationship was important because Ali Bux was not merely a relative; he was his teacher and guide. Under his training, the young musician practised seriously and gradually developed the control and skill needed for classical performance. Banaras therefore became linked with both his guru and his musical growth.

Choice A is correct because it gives the specific purpose of his arrival. He did not come for business, military service, or painting. Remembering the connection among childhood, Banaras, Ali Bux, and shehnai practice helps explain the beginning of his career. The answer also shows that great achievement generally grows through disciplined learning under an experienced guide.