LSAT Explanation PT 19, S4, Q19: Sponges attach to the ocean floor,

LSAT Question Stem

The statements above, if true, most strongly support which one of the following claims? 

Logical Reasoning Question Type

This is a Most Strongly supported question. 

Correct Answer

The correct answer to this question is C. 

LSAT Question Complete Explanation

This LSAT problem presents us with a passage that discusses two types of sponges, tubular and vase-shaped, and their ability to survive in different ocean current conditions. The passage states that these sponges were widespread during the late Jurassic period. The question asks us to determine which of the answer choices is most strongly supported by the statements in the passage. This is a Most Strongly Supported (MSS) question type.

First, let's analyze the passage. The main points are:

1. Tubular and vase-shaped sponges can live in slow-moving, quiet waters (because they can eject filtered water without assistance from ocean currents).

2. These sponges cannot live in strong currents (because their shape would cause them to be dislodged).

3. Both types of sponges were widespread during the late Jurassic period.

To help illustrate this, think of a calm pond where lily pads can easily float and thrive. If there were strong currents in the pond, the lily pads would be swept away and unable to survive. Similarly, these sponges can only survive in calm waters.

Now, let's examine the answer choices:

a) Few tubular or vase-shaped sponges lived before the late Jurassic period.

- The passage does not provide information about the number of these sponges before the late Jurassic period, so we cannot infer this statement.

b) Tubular and vase-shaped sponges were more common during the late Jurassic period than in succeeding geological eras.

- The passage does not provide information about the number of these sponges in succeeding geological eras, so we cannot infer this statement.

c) During the late Jurassic period, there were many areas of the ocean floor where currents were weak.

- Since tubular and vase-shaped sponges were widespread during the late Jurassic period, and they can only survive in weak currents, this statement is supported by the passage. This is the correct answer.

d) All sponges that are neither tubular nor vase-shaped inhabit areas of the ocean floor where there are extremely strong currents.

- The passage does not provide information about other types of sponges and their living conditions, so we cannot infer this statement.

e) No types of sponge live in large colonies, since sponges do not flourish in areas where much of the water has been filtered by other sponges.

- The passage does not provide information about the size of sponge colonies or their ability to flourish in areas with filtered water, so we cannot infer this statement.

In conclusion, answer choice (c) is most strongly supported by the statements in the passage. During the late Jurassic period, there were many areas of the ocean floor where currents were weak, allowing tubular and vase-shaped sponges to be widespread.