Assertion (A): Biological control is a method developed to treat plant diseases by using natural organisms or substances to control pests or pathogens. Trichoderma, a genus of fungi, serves as an example of such biological control agents. (✔ Correct)
Reason (R): Trichoderma are free-living fungi commonly found in the root ecosystem of plants. They act as biocontrol agents by competing with harmful pathogens and promoting plant growth. (✔ Correct)
Since both statements are correct, and the reason correctly explains the assertion, the correct answer is:
(A)