Some princely states in Karnataka had a degree of autonomy under:

Direct British rule
The Subsidiary Alliance System
Independent rule
French colonial rule

The correct answer is: B) The Subsidiary Alliance System.

The Subsidiary Alliance System was a system of indirect rule used by the British East India Company in India. Under this system, the British would provide military support to a princely state in exchange for control of its foreign affairs and the right to station British troops on its territory. The princely state would retain control of its internal affairs, but would be subject to British influence.

Some princely states in Karnataka, such as Mysore, Hyderabad, and Travancore, were part of the Subsidiary Alliance System. These states had a degree of autonomy, but were ultimately subject to British control.

Option A is incorrect because direct British rule was not the norm in Karnataka. The British did directly rule some parts of Karnataka, such as the city of Bangalore, but most of the region was under the control of princely states.

Option C is incorrect because some princely states in Karnataka were not independent. They were part of the Subsidiary Alliance System and were subject to British influence.

Option D is incorrect because French colonial rule was not a major factor in Karnataka. The French did have some influence in the region, but they did not directly rule any part of Karnataka.