Answer:
A
Explanation:
It is...
- Not B because the purpose of air guns is "to study beneath the ocean floor".
- Not C because according to the passage, the air guns make "very loud noises that can travel far".
- Not D because sentence 2 states that air guns are the "current way to study beneath the ocean floor".
Therefore, A is the best answer based on both the opening sentence and its supporting details that are mentioned towards the end of the passage.
Hope this helps you! Have a great rest of your day!
