Two — one to screw it most of the way in and the other to give it a surprise twist at the end.
or
Rootbeer.
or
Fifty — one to screw in the bulb and 49 to guard him/her.
or
Three skunks fighting over a pickle
First dog: My master calls me Furball. How about you?
Second Dog: My master calls me Sitboy
or
Chili
or
Seven months old.
or