Which Maratha clan established its rule over Gwalior?

The correct answer is B) Scindias.

The Scindias were a Maratha clan that established their rule over Gwalior in the 18th century. They were originally from the Malwa region of central India, and their founder, Mahadji Scindia, was a general in the service of the Maratha Empire. After the death of the Maratha emperor, Aurangzeb, in 1707, the Scindias became one of the most powerful Maratha clans. They expanded their territory and influence, and in 1731, Mahadji Scindia captured Gwalior from the Mughals. The Scindias ruled Gwalior for over 150 years, until they were overthrown by the British in 1858.

The other options are incorrect. The Holkars were a Maratha clan that ruled Indore, the Gaekwads ruled Baroda, and the Bhonsles ruled Nagpur.