Protein phosphatase 2A (PP2A) is a critical regulator of Cdk1 substrates during the cell cycle. The B55 subunit of PP2A influences the substrate selectivity, localization, and regulation of the enzyme. Given below are a few statements about PP2A and its regulation during the M-phase of the cell cycle.

A. PP2A-B55 activity is high during interphase but inhibited during early mitosis when M-Cdk activity rises.

B. M-Cdk1 turns off PP2A-B55 via the phosphorylation of an intermediary protein kinase called Greatwall.

C. M-Cdk1 turns on PP2A-B55 via the phosphorylation of an intermediary protein kinase called Greatwall.

D. When anaphase is initiated and M-Cdk1 activity declines, PP2A-B55 promotes dephosphorylation of Cdk1 substrates

Which one of the following combinations represents all the correct statements?