The correct options are
C progesterone
D oestrogen
The first contraceptive pill contained only synthetic oestrogen which made the woman naturally produce a higher amount of oestrogen as during pregnancy. This stopped the release of the egg from the ovary.
However, high levels of synthetic oestrogen in the body caused dangerous side effects such as blood clots, heart attacks, strokes, etc. In response, pill manufacturers, added synthetic progesterone. The pill now contains a small amount of oestrogen and a relatively larger amount of progesterone, hence the name “combined”.