Answer :
The answer to this question would be A. Proper documentation. You are giving credit to the people who helped you write your paper, and you are allowing the readers of your paper to visit those websites/ read those books, for further information
I believe the answer is "proper documentation."
You would still be able to refer back to your sources even if you just had list of links(not a works cited), having a works cited does not ensure that you have reliable sources(all of your sources in a works cited could be Wikepedia(i.e. not reliable)), and a works cited does not ensure a well-written research paper(you could have a terrible paper, but still have a correctly formatted Works Cited. The point is, having a works cited will not improve the quality of your research paper).
Hope this helps!
You would still be able to refer back to your sources even if you just had list of links(not a works cited), having a works cited does not ensure that you have reliable sources(all of your sources in a works cited could be Wikepedia(i.e. not reliable)), and a works cited does not ensure a well-written research paper(you could have a terrible paper, but still have a correctly formatted Works Cited. The point is, having a works cited will not improve the quality of your research paper).
Hope this helps!