A really good intro should include the main topic, points you are going to talk about, a thesis statement, a hook, and maybe a rhetorical question. Just make sure you stay on topic.
Correct answer is B for this question
No. "Children in the dark make mistakes" does not have the same meaning as "Mistakes in the dark make children." The first implies that without sufficient light, children would make mistakes, while the second implies that if you make mistakes in the dark, you'll have children.
The opposite of this sentence: "Children in the dark make mistakes", should be "Mistakes are made when Children are in a dark area".
hope this helps