Choose the most effective word or phrase within the context suggested by the sentence.

4. The student was _________________ regarding his plans after graduation.

A) on the fence

B) undecided

C) unable to make a decision

4. The correct choice is B.

Choice A is slang and not appropriate for most writing. Choice C is wordy and possibly includes more than was intended as judged from the remainder of the sentence. Choice B is a clear word choice.