Which small group format generally selects members because they are experts on the issue being discussed?

Panel discussion.

Explanation:

A panel discussion requires a small group of people (typically 3-4 experts or practitioners in the field) to gather and discuss about an specific topic in front of an audience.

the major pests we deal with are insects, weeds and fungal diseases. a pesticide is a product, whether organic or chemical, used to kill the target pest. there are other techniques gardeners should use that can prevent the severe infestations that make the use of pesticides necessary

d) a person who learns about the world by observing it.

explanation:

scientist are people who discover why and how things are done and made in the world.