What impact is presented when users reveal their passwords to people stating they are from tech support?

A$.$It exposes the passwords to brute$-$force attacks from malicious hackers.

B$.$It provides technical support staff with access to the user's personal files stored on the network.

C$.$It exposes users to social engineering attacks that try to gather login credentials for malicious use.

D$.$It prevents the user from needing to change a password following the password history component of the policy.