Jan Needed a New Phone So She Went to the Phone

Jan needed a new phone so she went to the phone store where they offered her the latest Samsung for 50 dollars. She agreed to buy the phone. Then they told her that she would have to sign a new contract for 80 dollars a month. Jan has just experienced

A) the fundamental error
B) the central route of persuasion
C) the door-in-the-face technique
D) the foot-in-the-door technique
E) lowballing