Well I don't see any options so my guess would be:
Don't pick any opinions because if your writing a research paper then you should have your paper based off of facts and things you have seen off of the internet.
The pet cloning controversy. If you were writing paper about pet cloning, which one of these sentences from the passage would be irrelevant and NOT supported by research
And when the rulers died, the Aztecs buried them there and built a pyramid over them. The pyramids now stand like small mountains, though they were made by hand. And so they named it Teotihuacan, because it was the burial place for the rulers.
