I wrote my corporate finance final yesterday afternoon. It is really great to have my two biggest exams off my back, and only two more to go. Yesterday before I wrote the exam I was writing some old exams to practice. These old exams are usually fairly good practice material assuming that they don't date from the mid 1990's.

As I looked at the multiple-choice section I came across a question that I had no clue at all how to answer. Here it is:

The answer clearly is (a) because it is circled in the marking key, but what are the ramifications of having a "only a) is true" answer.

Does it mean that if I circle (a); I acknowledge that (a) is true but am unwilling to accept that (b) is false?
What happens if I circle (c) on the exam, am I wrong?

This is the type of question that could keep me up at night. Luckily I didn't find this question until right before my exam so I didn't lose any sleep over it. On the real exam I may have guessed on a couple questions in the multiple-choice section, but at least there were no questions like this.