Evaluate the role of HCG and progesterone produced by the placenta in pregnancy.

• A. HCG decreases maternal metabolism, while progesterone strengthens fetal bones.
• B. HCG triggers maternal antibodies, while progesterone initiates labor.
• C. HCG maintains the corpus luteum, while progesterone stabilizes the uterine lining.
• D. HCG stimulates fetal heart rate, while progesterone forms the amniotic sac.

Answer: (C)