Fraternal twins form when
A) a sperm splits in half and fertilizes two eggs that have been released at the same time.
B) a single egg that is fertilized by two different sperm splits in half and develops into two fetuses.
C) two eggs are released at once and fertilized by two different sperm.
D) a single egg, fertilized by a sperm, splits in half and develops into two fetuses.

Question

Quizplus · Accepted Answer

Fraternal twins are formed when two eggs are released at the same time and are fertilized by two different sperm. Therefore, option C is the best choice. Option A is incorrect because one sperm cannot split in half to fertilize two eggs. Option B is incorrect because it is extremely rare for a single egg to be fertilized by two different sperm. Option D is incorrect because a single egg splitting in half after fertilization leads to identical twins, not fraternal twins.

Fraternal Twins Form When