Please help.
An example of a single-gene trait is

A. bands on a snail’s shell.
B. beak size in the Galápagos finches.
C. length of snails.
D. fur color in cats.

Which of the following explains why the edges of Africa and South America fit together like two pieces of a puzzle?

A. endosymbiosis
B. biological forces
C. continental drift
D. None of the above