The expression of cell cycle restriction point is WRONG
选项：

A:Restriction points are not necessary for normal cell cycle function.;
B: Restriction points are necessary for cycling cells with DNA damaged;
C: Cell cycle has four restriction points: G1/S, S/G2, G2/M and M/ G1;
D: The most important is the G1/S limit point;
E: It acts as a "brake" that stops the cell cycle when the cell encounters environmental pressure or DNA damage, and "checks" the cell before entering the next phase.