How can biological control of insects be done?

Which one of the following is an example of carrying out biological control of pests/ diseases using microbes ?

Explain the basis of biological control of weeds.

Explain biological control of pests and plant pathogens with examples.

Describe the main ideas behind the biological control of pests and diseases.

How does the biological control help in ecosystem stabilization?

Name the fungus which is in biological control of other fuungi. How it is harmful to humans?

Which one of the following proved effective for biological control of nematodal disease of plants ?