Physiology Which of the following is true during the 12-hour period preceding ovulation? A A surge of LH is secreted from the pituitary B The surge occurs immediately after the formation of the corpus luteum C The surge is followed immediately by a fall in the plasma concentration of progesterone D The number of developing follicles is increasing 💡 Explanation Which of the following is true during the 12-hour period preceding ovulation? ✓ Correct Answer: A. A surge of LH is secreted from the pituitary