^ Same as above. I'm not sure why option E is correct, since I think "research based on xx" and "research on xx" have 2 different meanings.
"Research on xx" means you're researching xx subject, whereas research based on xx might mean you're researching on other topic, but using evidences from xx subject
"Research on xx" means you're researching xx subject, whereas research based on xx might mean you're researching on other topic, but using evidences from xx subject












