In order to encourage participation in a walkathon, the organization arranging the event offers free items, such as a T-shirt or a water bottle, to all the participants. Which of the following principles of influence is being used?

A. liking

B. authority

C. scarcity

D. reciprocation

E. social proof

The correct answer is letter "E": social proof.

Explanation:

In marketing, Social Proof is nothing more than a demonstration of the use of a product or service by a group of people so others can be encouraged to purchase it. Social proof has proven effectiveness as a way to influence others and every time on the internet and social media it tends to facilitate businesses more leverage more over at the moment of introducing goods in the market so more people are willing to buy those products or services.