What could increase by cutting forests and expanding cultivation?

Correct answer: Food crops and cash crops

The direct answer is A, food crops and cash crops. When forests are cleared, the land can be used for cultivation. Farmers may grow food crops such as rice, wheat or maize for eating, and cash crops such as cotton, jute, tea or sugarcane for selling in markets. Under colonial rule, expanding cultivation was encouraged partly because it could provide revenue through land taxes and supply commercial crops. Option A is correct because both food and market-oriented crops could be produced on newly cleared land. Option B, sea fish, comes from seas, rivers or ponds, not from clearing forests for fields. Option C, stone clouds, is not a real agricultural product or natural category. Option D, sand books, is also meaningless and cannot be produced by farming. The key chain is: forest cleared → land becomes fields → crops are grown → food and saleable produce increase. Memory cue: cultivation gives crops; markets give cash crops.