The correct option is C Trichoderma, Baculovirus, Bacillus thuringiensis
Biocontrol of pests is the method of controlling pests that relies on natural predation rather than introducing chemicals. It greatly reduces our dependence on toxic chemicals and pesticides.
The bacterium Bacillus thuringiensis (Bt) is a microbial biocontrol agent used to control butterfly caterpillars. These are available in sachets as dried spores which are mixed with water and sprayed onto vulnerable plants such as Brassica and fruit trees, where these are eaten by the insect larvae. In the gut of the larvae, the toxin produced by the bacterium is released and the larvae gets killed.
Nucleopolyhedrovirus is a genus belonging to baculoviruses. They are pathogens of insects and other arthropods. They are used as biological control agents. These are species-specific, narrow spectrum insecticidal applications.
Fungi belonging to the genus Trichoderma are used as biocontrol agents that are well-known for their roles against various plant fungal pathogens such as Phytophthora, Fusarium, etc.
Nostoc, Azospirillum, Oscillatoria, Rhizobium are biofertilisers. They enhance the nutrient content in the soil.
Tobacco mosaic virus infects a wide range of plants, especially tobacco and other members of the family Solanaceae.
Aphids are pests that suck the sap of plants.