Answer:
The term that best describe the change in Idri's Behaviour is Normative conformity and compliance.
Step-by-step explanation:
In psychologial terms, Normative conformity is described as change in an individual in it's attitude or behaviours that is made to fit in a determined social group, in this case, Idris in order to fit in the group he decides to drink fearing social rejection. Also, Compliance is defined as a change in one's attitude or behaviour while still not actually wanting to or disagreeing with the social group, in this case, Idris decides to drink even though he still feels that drinking is problematic, therefore also Compliance is present in his behaviour.