Question

a typical pregnancy test detects the presence of
a fetal hemoglobin
b estrogen
c hcg
d a corpus luteum

Explanation:

Pregnancy tests detect human chorionic gonadotropin (HCG). HCG is a hormone produced by the placenta after implantation. Fetal hemoglobin is related to the fetus's blood - carrying capacity. Estrogen is a sex hormone with various functions in the body but not the target of typical pregnancy tests. The corpus luteum is a structure in the ovary.

Answer:

C. HCG