If the stress Female rhinoceroses suffered does have effect on
their fertility, then the author could not for sure say that
"Probably, therefore, some substance in the tranquilizer inhibits
fertility."
We can think it in this way:
A is short for Substance. B is short for Stress.
The author try to prove that A lead to the result, but before that
he must state that B could not lead to the result. If not, his
conclusion will not be convincing.
So option C appear to be the most suitable. |