Which of the following events are a part of a menstrual cycle?
i. The pituitary gland stimulates the ovaries to produce oestrogen and progesterone
ii. Ovulation takes place
iii. Oestrogen stimulates the uterus to build up extra tissue and blood layer to make the wall nutritious for a zygote
iv. In the absence of fertilisation, the egg is eliminated from the body along with the uterus lining which comes out as blood discharge at the time of menstruation