After ovulation, progesterone from the corpus luteum
- A. maintains the thickened endometrium ready for implantation
- B. immediately triggers menstruation
- C. stimulates a second ovulation
- D. dissolves the zona pellucida of the egg
Explanation
Progesterone makes the endometrium glandular and rich in blood supply, the state needed for an embryo to implant. Menstruation follows only when the corpus luteum fails and progesterone levels drop.