This question is incomplete because you are missing the stages, here is the complete question
All of the following stages must occur for a woman to get pregnant. However, after which stage can a woman be described as pregnant?
A.Menstruation
B.Implantation
C.Ovulation
D.Intercourse
According to this, the correct answer is B. Implantation
Step-by-step explanation:
Gestation or pregnancy occurs as a fetus or embryo develops inside a woman, this period lasts for about 40 weeks in humans and begins with the implantation that refers to the moment a fertilized egg attaches to the uterus, and therefore a new life begins to form from this. The implantation is only possible after the ovulation has occurred and the ovule produced has been fertilized. However, only after implantation, a woman is said to be pregnant because only when this happens cell begin multiplying which leads to the formation of tissue and organs in the fetus over time. Thus, it is implantation the stage after which a woman can be described as pregnant.