Cancer is essentially a never-ending repetition of the s phase of the cell cycle. unregulated mitotic cell division. the binding of cyclins and cdks. the creation of extra checkpoints in the cell cycle.

The answer is unregulated mitotic division.

This occurs due to the failure of tumor suppressor factors such as the p53 proteins. These tumor suppressors are involved in the checkpoints of cell cycles especially when they are damage to DNA. They are also involved in the apoptosis of such cells. The unchecked activation of cyclin-dependent kinases causes unregulated progression of mitosis.

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.

i believe the answer would be b. hope it : )