Gautamiputra Satakarni became famous for defeating which Shaka ruler?

Correct answer: Nahapana

Gautamiputra Satakarni was a prominent ruler of the Satavahana dynasty in the Deccan. His achievements are known partly from inscriptions and coins, including evidence of conflict with the Western Kshatrapas, a Shaka-linked ruling power. He is especially associated with defeating Nahapana and recovering territories and influence that had been held by Nahapana’s side. This episode is important because it illustrates competition between Satavahana rulers and Shaka or Western Kshatrapa authorities in western India.

The correct choice is C, Nahapana. Rudradaman was another important Western Kshatrapa ruler and is known from the Junagadh inscription, but he is not the ruler identified in this standard account of Gautamiputra’s major victory. Menander belonged to an earlier Indo-Greek context, while Kanishka was a Kushan ruler. The names represent different political powers and periods, so remembering the Satavahana–Western Kshatrapa conflict helps select Nahapana.