The one that is the best way to find the correct answer for a sentence completion question on a reading test is : c. look at the main parts or the paragraph and infer the answer
The main parts is basically the core of the content. If you find it, it would be really likely that you could answer a question about it
hope this helps
A "popular press source" in general refers to any news publication, either on paper or online, that has a wide circulation and is popular. Although this doesn't always mean that it is reputable.
I think it's B, but I can't guarantee it... Sorry
