Answer:
D. smart phone
explanation;
a. what the heck is a radio going to do?
b. an HD television? is his job watching movies?
d. he already has a form of communication he uses, he needs something that can to both things at the same time
c. a smart phone can do everything he needs to do, likely faster than a landline phone or laptop.
"To preform specific useful computing tasks, like word processing and calculation" is the correct answer. This is the whole purpose of system software. The third answer is some other type of software(third party software?) and the fourth answer is most likely a compiler. Those are the easiest to take off. The second could also work.
The two answers I would go with are the first and the second.