Hi, really need help, it’s a simple question, pls someone.

Answer:
B
Explanation:
Is source of Lava all you are going to put in the second section? If it is, that eliminates both the first and last ones. Part 2 is always safe, no matter what comes next.
If it's a science report, part 2 is safe. I think I'd pick it. Dull but it directs the reader to a change.