The relationship between feudatory states and the British was often marked by:

The correct answer is: d) All of the above

The relationship between feudatory states and the British was often marked by treaties and alliances, conflicts and power struggles, and economic cooperation.

• Treaties and alliances: The British often entered into treaties and alliances with feudatory states in order to gain their support. For example, the British East India Company signed a treaty with the Mughal Empire in 1707. This treaty gave the British Company the right to trade in Mughal territories and to establish factories there.
• Conflicts and power struggles: The British and feudatory states often clashed over power and resources. For example, the British East India Company fought a series of wars against the Maratha Empire in the late 18th century. These wars resulted in the British gaining control of much of the Maratha territories.
• Economic cooperation: The British and feudatory states also engaged in economic cooperation. For example, the British East India Company traded with feudatory states for raw materials, such as cotton and indigo. The British also invested in infrastructure projects in feudatory states, such as railroads and canals.

The relationship between feudatory states and the British was complex and varied. It was marked by treaties and alliances, conflicts and power struggles, and economic cooperation.