The correct answer is: A. Bihar Sharif (Nalanda)
Dargah of Makhdum Hazrat Sultan Ahmed Charampose is situated in Bihar Sharif, Nalanda district, Bihar, India. It is a popular pilgrimage site for Muslims. The dargah is said to be the tomb of Makhdum Hazrat Sultan Ahmed Charampose, a Sufi saint who lived in the 13th century. The dargah is a complex of buildings, including a mosque, a library, and a guesthouse. The main building of the dargah is a large, domed structure. The interior of the dargah is decorated with intricate tile work and calligraphy. The dargah is open to visitors from all faiths.
Option B is incorrect because Nawada is a district in Bihar, India. However, the dargah of Makhdum Hazrat Sultan Ahmed Charampose is not located in Nawada.
Option C is incorrect because Sitamarhi is a district in Bihar, India. However, the dargah of Makhdum Hazrat Sultan Ahmed Charampose is not located in Sitamarhi.
Option D is incorrect because Gopalganj is a district in Bihar, India. However, the dargah of Makhdum Hazrat Sultan Ahmed Charampose is not located in Gopalganj.