Regarding the Reduction of the Impact of Moral Hazard by Insurers,which

Regarding the reduction of the impact of moral hazard by insurers,which of the following is true?

A) Insurance companies lessen the impact of moral hazard by requiring that individuals with insurance make co-payments or pay a deductible.
B) The only avenue for insurers seeking to reduce moral hazard is through the use of deductibles.
C) It is not possible for insurers to reduce the risk of moral hazard,and this is seen as a risk of doing business.
D) The only avenue for insurers seeking to reduce moral hazard is through refusing to insure those who have previously made multiple insurance claims.
E) Insurers refuse to pay claims believed to result from the effects of moral hazard.