The Foot-In-The-Door Technique Is a Method Of

The foot-in-the-door technique is a method of:

A) encouraging people to do a small favor after they've refused to comply with a larger request.
B) encouraging people to do a favor for us after we have granted them a small request.
C) encouraging people to do a larger favor after they've agreed to an initially small request.
D) using increasingly larger rewards to encourage people to comply with increasingly larger requests.