Mark Would Like to Hang Out with His Friends After

Mark would like to hang out with his friends after school, but he goes home to work on his term paper that is due next week. He knows that he needs to do the term paper first and then hang out with his friends. Mark is:

A) exhibiting a lack of unconditional positive regard for his friends.
B) deferring immediate gratification for a desirable future outcome.
C) demonstrating an external locus of control.
D) doing all of the above.