Social media allows businesses to use which proven marketing principle? select one: a. reciprocity b. social proof c. authority d. scarcity

B is the most reasonable one

Solution:

The right answer is B (Social proof).

Social proof  is the influence that the actions and attitudes of the people around us (either in real life or online) have on our own behavior. The "proof" element is the idea that if other people are doing it .

This is the required right answer.

(because i need 20 chars)