For the "which one of these was mentioned in the passage" questions, then like others have said all of the information will be explicitly stated in the passage, and it's just a matter of finding it. The "author would most likely agree with" questions are essentially extensions of the main point questions, and are probably the hardest of the RC sections in that they're just the sort of questions that either seem right to you or don't. My recommendation: read. Just read anything, but read a lot. People say RC is the hardest section to study for...I guess I'm lucky in that it's never been a problem for me. I don't have any specific advice to offer, but as far as I can tell, reading a lot of different kinds of material - literature, scientific articles, historical works, and whatever else - is the only way to "get it" for RC. At some point it should just start making sense.