The correct answer is option (3), because in a 28 days menstrual cycle of a human female, rapid secretion of LH leading to its maximum level during the mid-cycle ( 14‌th ‌ day) called LH surge induces the rupture of Graafian follicleand thereby the release of ovum (ovulation). Hence, both (A) and (R) are correct and (R) is the correct explanation of (A).