Withdrawal of which of the following hormones is the immediate cause of menstruation ?

After ovulation the ruptured follicle forms the corpus luteum, which secretes large amounts of progesterone.
Progesterone is essential for the maintenance of the thickened, secretory endometrium of the uterus.
If fertilisation does not occur, the corpus luteum degenerates towards the end of the cycle.
The level of progesterone in the blood then falls sharply.
Without progesterone the endometrium cannot be maintained; it disintegrates and is shed along with blood, which is menstruation.
The fall of oestrogen also contributes, but the immediate cause is the withdrawal of progesterone.
So the hormone is progesterone.