Progression Through the Cell Cycle Is Controlled at Checkpoints, Which

Progression through the cell cycle is controlled at checkpoints, which are regulated by interactions between cyclins and cyclindependent kinases. Genes that control the cell cycle are frequently mutated in cancer cells.
-What would be the most likely effect of a mutation that causes cyclin B to be unable to bind to CDK?

A) Cells pass through the G2/M checkpoint and enter mitosis even when DNA has not been replicated.
B) Cells never pass through the G1/S checkpoint.
C) Cells pass through mitosis more quickly than unmutated cells.
D) Cells fail to pass the G2/M checkpoint and do not enter into mitosis