Select the best answer for the question.

$18.$ To make a case based on $,$ the employee must demonstrate that the employer or a representative of the employer promised the employee job security despite the apparent at$-$will nature of the employment relationship.

A$.$ an implied$-$in$-$fact contract

B$.$ promissory estoppel

C$.$ in pari delicto

D$.$ a quasi$-$contract