I do not think that this is on the BMAT syllabus anymore but more the knowledge, the better!
Oestrogen – thickens the lining of the uterus.
Progesterone – maintains lining of uterus
If there is fall in progesterone, the lining of uterus would break down.
So the order must be:
Rise in oestrogen High conc. of progesterone Fall in progesterone conc.
So the answer is C.