DO CHALLENGE THE QUESTION MORE AND MORE !
THE ANSWER SHOULD BE 'EXIT THE CELL CYCLE'
EXPLAINATION: in updated NCERT FIG 10.1 PAGE NO.163 G0 is clearly shown to be outside the cell cycle. Further there are 2 types of G0 cells- Reversible and Irreversible.
Reversible ones can continue the cell cycle but majority are irreversible which EXIT cell cycle permanently.