Answer :
The correct answer is A. mopped his brow, exhaled sharply, and picked up his phone. This is the complete predicate because it includes both the predicator (the main verb), and all other things that follow and are used to describe the verb. In this case, all three are equally important and are parts of the predicate.
Looking up from his computer monitor, Jason mopped his brow, exhaled sharply, and picked up his phone. Complete predicate: mopped his brow, exhaled sharply, and picked up his phone.