When restraining a rat, you should never

A. hold the rat so that breathing is unimpeded.

B. grasp the end of the tail.

C. grasp the base of the tail.

D. grasp the neck by placing thumb and forefinger around the lower jaw.

The correct answer is B. Grasp the end of the tail. You should do what is described in D but if you just hold it buy the tip, there's a chance that it might fall of or that you might rip it off which can be bothersome both for you as a scientist and for the rat who would be traumatized and might not be usefull for research anymore.