Well, this answer can be many things! I would say "When you read carefully in order to determine the meaning of a challenging word, you are 'using context clues'", perhaps? Maybe not...how about "...using prior knowledge"? Since you didn't offer any alternative answers, or list any answers, I can only guess. I hope I helped you a little bit!
The subject tells whom or what the sentence is about, and the predicate tells what the subject is or does.
Example: The dog ran.
Explanation: The dog is the subject of the sentence, because the sentence is telling something about that dog.
Answer: um this is kinda a personal question so it depends how you answer it because it says you not me.
Sorry I can’t help