What was one main reason for tension between forest officials and local people?

Correct answer: Government rules and restrictions on local uses increased

A major source of conflict was the growing control of the colonial forest department over how villagers could use forests. Local people traditionally depended on forests for fuelwood, fodder, fruits, leaves, grazing, small timber, and other everyday needs. Officials increasingly treated forests as state property and introduced rules that limited or sometimes prohibited these customary practices. As a result, activities that had earlier been part of ordinary life could be labelled illegal, and people faced penalties or loss of access.

The other choices do not explain the tension: forests were not made completely free, local people did not simply end timber trade, and forests certainly contained useful resources. Therefore, option D is correct because increased government rules and restrictions on local uses directly interfered with established livelihoods and created resentment between officials and forest-dependent communities.