The answer is private acceptance and public compliance.
Hence, the correct sentence is:
Informational social influence is to private acceptance, as normative social influence is to public compliance.
'Informational Social Influence' is also known as social proof.
It usually happens when we are in a given situation and do not understand what to do or are not sure of our own ability to know what to do.
In such cases, we look for social poof in order to understand a situation and find a solution.
