Answer:
An interview with a scientist.
Explanation:
Primary sources are considered original documents, contemporary to the event or period to which they refer. That is, a primary source can be considered an original record of something. If so, if you are writing an article about global warming, you could use an interview with a scientist as your primary source. This is because an interview is the first record of this moment, that is, it is an original source, without adaptation.
