Which of the following is the strongest evidence that cytokinins regulate cell divisions?

A) induction of root growths in tissues exposed to cytokinin
B) induction of shoot growths in tissues exposed to cytokinin
C) decrease of cyclin gene expression in tissues exposed to cytokinin
D) ability of cytokinin to interact with auxin at the molecular level and change auxin biosynthesis and transport
E) increase of cyclin gene expression in tissues exposed to cytokinin