Answer: A, "I could look for excerpts that connect to the claim in a relevant way."
Explanation: You want a source you can trust, magazines and articles aren't always trustable, you don't want fake sources and you don't want to make up facts.
Independent clause this is because they is the subject , know is the verb so simply is the adjective. all a sentence need to stand on its own is a noun and a verb :)your welcome
In my opinion, you can use it to define words and find more suitable words (they usually have a thesaurus built into the definition), and find words that seem more elegant or mature.