Question

Here is the first paragraph. It has two sentences.

This is the second paragraph. It also has two sentences.
This is the third paragraph, consisting of a single sentence.

The missing element is... Which one

Answer 1

I don't quite understand, you need to give us the full options with the question a bit more clearer

Answer 2

Answer: it is <p></p>

Explanation: guessing didn't pay off : (