The answer is A. relies on a variety of credible primary and secondary sources including books, articles, and multi-media. A solid research paper should have as much research included as possible, but you need to make sure it is credible and reliable. It doesn't matter how recently the resource was written, as long as it reliable, so the answer isn't B. Your research can be from anywhere you can find it, even on the internet, as long as it's credible, so it's not C. Although you can usually count on Encyclopedias and books to be reliable, they don't have to be your only sources of information, so the answer isn't D, either. The key to a good research report is good, credible research.