The answer is expel an unfertilized egg and endometrium
Explanation:
The menstrual cycle consists of a series of regular changes that naturally occur in the female reproductive system which make pregnancy or menstruation possible. During the first phase of the menstrual cycle, the endometrium is released along with an amount of blood, this bleeding is a sign that a woman is not pregnant.
The answer to fill in the blank would be B) aka the second option because food gives our body energy and serves as fuel to recharge to give us energy to do things.