When Would You Need to Change Your Field Site

When would you need to change your field site?

A) if you are observing in a public location and some people don't agree to participate
B) if you are conducting ethnography and a peripheral member of the group doesn't agree to participate
C) if you are observing in a private location and a peripheral member of the group doesn't agree to participate
D) if you are conducting ethnography and an important member of the group doesn't agree to participate