Bacillus thuringiensis is used to control

Explanation:

• Bacillus thuringiensis is a bacterial species inhabiting soil.
• Bacillus thuringiensis produces proteins that are toxic to insects when ingested.
• Bacillus thuringiensis is widely used in agriculture for controlling insect pests.
• The endotoxin in a crystalline inclusion and other proteins produced by the Bacillus thuringiensis are involved in host invasion and blocking their immune defense.
• Endotoxin is lethal to insects orders like Lepidoptera, Diptera, and Coleoptera.

Final Answer:

Hence, the correct option is D: i.e. insect pests.