Answer:
It has two paragraphs: one for the thesis and one for background.
Explanation:
Paragraph 1: Thesis states the claim "Of all the mysteries in the world, none has been as popular as that of the Loch Ness Monster." we can determine that the first paragraph is the thesis (because most are).
Paragraph 2: gives background on the story, where it originated, and why it is such a great mystery.