Aresearch paper writer into an argument supporting a. synthesizes, thesis. b. reports, sources. c. notes, synthesis. d. sources, works cited.

The answer is actually A. You can list sources, sure, but a writer would want to combine (aka synthesize) all of the different knowledge they gained from reading reports into one paper. In order to write a paper, you mist have a thesis, or a claim, that is the main focus of your paper. Everything the writer would research would be to support their thesis, not the sources.