which, in which, of which

[Nami Nami]

Dear teacher,

1. Which is correct?
2. If all are correct, which is more common?
3. Do I need to put a comma after "team"?

Thanks.

A. The jury is a team which the members are picked from the normal people ...
B. The jury is a team in which the members are picked from the normal people ...
C. The jury is a team of which the members are picked from the normal people ...

[Alan]

C.

No comma is needed.