Q1 - French divers recently found

[nneamakaeze]

Im having trouble seeing how B is right. I personally thought it was D. Could u please explain all answer choices and help me understand why B was the best choice?

[ManhattanPrepLSAT1]

Let's look at the problem this way. There are stalagmites in the cave, which they tell us means that there was no water in the cave when the stalagmites were being formed. We know this because stalagmites form when water falls from above. If the cave were full of water, we wouldn't get falling water on one spot forming stalagmites.

So we know the cave wasn't always full of water. If water wasn't present in the cave, then the water level had to be lower. This leads directly to answer choice (B).

(A) is the exact opposite of what we know to be true. The water level was lower, not higher. But this answer choice does at least get us thinking in the right direction.

(B) we know the water level had to be lower in order for the stalagmites to have formed.

(C) maybe they were the first, maybe the spot has been visited for ages. We don't know.

(D) why would we suspect there was another entrance? Maybe if a ship had been found in the cave and the ship wouldn't have fit in the under water entrance, but even then, maybe the entrance had undergone significant changes. No need for another entrance to explain the stalagmites.

(E) maybe if the cave was not filled with water, and there were no new stalagmites, this answer choice might make sense, but the cave is filled with water and we don't know whether new stalagmites could potentially form.