Which of the following questions might a communication researcher ask about an advertisement?

A) Does the advertisement work?
B) How much did the advertisement cost?
C) Who paid for the advertisement?
D) Is this the best product?

Communication researchers are interested in understanding the effectiveness of different types of messages, including advertisements. Therefore, the question "Does the advertisement work?" is the most relevant for a communication researcher. The other options (B, C, and D) are more relevant to financial or marketing researchers.