I would think it's one of the last two. It is a news article which means it would be important to verify facts and information so that it would be considered trustworthy and you could do this through evidence.
Hope that helps :)
I believe the correct answer is B.
Filling a prescription is going to a pharmacy and getting more medicine. For example, you go to the doctor for an infection and he/she gives you a paper to take to the drugstore that says what medicine you should take, how much, and how often. The paper is the prescription (Most places do this electronically). The drug store people put your pills in a bottle. This is filling the prescription.