Final answer:
Source 1 begins with an interesting fact as a hook.
Step-by-step explanation:
The correct answer is A. Interesting fact. Source 1 begins with an interesting fact that captures the reader's attention and hooks them into reading further. This is a common technique used in writing introductions to engage the reader and make the introduction more entertaining. By starting with an interesting fact, the writer can establish intrigue and create curiosity, encouraging the reader to continue reading.