The correct answer is D. Rajgir.
Rajgir was the capital of the Magadha kingdom during the time of Jarasandha. It is located in the present-day state of Bihar, India. The city was founded by Ajatasatru, the son of Bimbisara, and was the seat of power for the Magadha kingdom for over 200 years. Rajgir was an important center of learning and culture during the time of Jarasandha. It was home to many Buddhist and Jain monasteries, and was also a popular pilgrimage destination. The city was eventually abandoned in the 12th century, but it has since been rediscovered and is now a popular tourist destination.
Madhepura, Banka, and Jamui are all located in the state of Bihar, India. They are all important historical and cultural sites, but they were not the capital of Jarasandha’s kingdom.