Answer:
I think its B
Explanation:
since a professor has already written books on the production of food he should be well prepared for writing an article. People who already write have a better ability to grab a reader's attention.
the tv reporter has only visited a single fast food museum, so he wouldn't have much to write on.
the former worker is already mad at being fired (he would write negatively about the place) and only has knowledge about meat. (in my opinion)
the senator could be a good option but his field is law not writing.
hope this helps :-)
