Human chorionic gonadotropin (hCG) is produced by which of the following?

Human chorionic gonadotropin (hCG) is primarily produced by the placenta after implantation of the embryo. This hormone is crucial for maintaining pregnancy in its early stages, as it supports the corpus luteum, which produces progesterone necessary to maintain the uterine lining and prevent menstruation.

During early pregnancy, the presence of hCG in the mother's blood or urine is what pregnancy tests detect. The hormone ensures that the body maintains an environment suitable for fetal development until the placenta is fully developed and can take over hormone production.

In contrast, the ovaries produce hormones such as estrogen and progesterone but do not produce hCG. The hypothalamus plays a role in regulating hormonal activities but is not directly involved in the production of hCG. The anterior pituitary gland produces several hormones related to reproductive functions but does not produce hCG either. Thus, the correct answer reflects the specific source of hCG during pregnancy.