How dose lock-and-key mechanism relate to hormones?

Question

A. If a hormone fits the receptor site, then there is no reaction. If a hormone and a receptor site do not match, then there will be an effect.

B. If a hormone fits the receptor site, then there will be an effect. If a hormone and a receptor site do not match, then there is no reaction.

C. No effect will occur regardless of weather the hormone does or does not fit the receptor site

D. None of the above

Answer 1

http://blog.udemy.com/lock-and-key-hypothesis/

Answer 2

so whats the answer then

Answer 3

It's B.
Trust me. I did the test and got it right.