If you are trying to persuade someone using the principle of reciprocity, it is important to know that the reciprocity technique is more likely to be persuasive

The correct answer is: When people had already been benefit or helped by you.

Explanation:

The reciprocity technique states that most individuals are psychologically driven to return favors done to them. This is a predisposition studied in social psychology for over the years. People feel compelled to return good deeds done to them. So, if a CEO of a company wants to persuade someone using the principle of reciprocity, first he/she has to do something for them, maybe giving them a service for free, so that the user will feel compelled to help, invest in the company in return.

In conclusion, it is important to know that the reciprocity technique is more likely to be persuasive when, you've already helped or benefit the person or the individual that you want to persuade using the principle of reciprocity.