Question

It is an election year, and a volunteer asks if you would put a small, one-foot sign in your yard. you agree. the next week, your wife cannot believe you agreed to let the volunteer put a new, three-foot sign on the front lawn. this technique is known as the _____.

Answer 1

this technique is known as the: feet-in-the-door phenomenon

Feet-in-the-door refers to a situation when someone feels inclined to do a biger favor because they had previously agreed to do a smaller favor.
Many marketing salesmen utilize this technique in order to increase the sales of their product.