They have to fit in where you put them
Learning is taking in new facts, while studying is looking over stuff you already know to prepare for a test. For example: You look over flash cards while studying to remember things you already know. While st school, you take in new information.
You can grab your audience's attention by starting your essay off with a question, a quote, an interesting statement, etc.
The answer is C, they present the problem in the first part of the sentence (rather than...) and provide a solution in the second half.
