Which fungus plays the role of a biological control agent in cotton bollworm?

Correct option is D

Beauveria bassiana is a fungus that serves as a biological control agent in managing the cotton bollworm (Helicoverpa armigera). This fungus is used as a biopesticide to control the population of bollworms, which are destructive pests of cotton crops. Beauveria bassiana infects and kills the bollworm larvae, providing a natural and environmentally friendly approach to pest control.