---Are you worried when your son often plays computer games ?
-----Yes , I think playing computer games ______________ teenagers .
A. has a good effect on B. have a bad effect to
C. has a bad effect on D. has a bad effect for
---Are you worried when your son often plays computer games ?
-----Yes , I think playing computer games ______________ teenagers .
A. has a good effect on B. have a bad effect to
C. has a bad effect on D. has a bad effect for
C