The following graph represents the concentration of cyclins over the course of the cell cycle. Which of the following statements is TRUE regarding the cell cycle where the red arrow is pointing?a)CDK proteins are actively phosphorylating and activating cyclins so that the cell will properly assemble the spindle apparatus.b)CDK proteins are actively phosphorylating proteins that are involved in DNA replication.c)CDK proteins are actively phosphorylating proteins that are responsible for assembling the mitotic spindle.d)CDK proteins are actively phosphorylating regions of the DNA that need to be targeted for DNA repair.e)CDK proteins are actively phosphorylating and activating cyclins so that the cell will prepare to replicate its DNA.