LSAT Explanation PT 27, S1, Q19: Pollen and other allergens can cause

LSAT Question Stem

If the statements above are true, which one of the following must also be true? 

Logical Reasoning Question Type

This is a Must Be True question. 

Correct Answer

The correct answer to this question is E. 

LSAT Question Complete Explanation

First, let's analyze and summarize the information in the passage. The passage tells us that pollen and other allergens can cause cells in the nose to release histamine, which leads to allergy symptoms like runny nose, congestion, and sneezing. Antihistamines can help minimize these allergy symptoms by blocking histamine's action. However, antihistamines also have other effects, such as drowsiness. Importantly, the passage states that histamine does not play a role in how colds produce their symptoms.

To simplify this, imagine a situation where a person is exposed to pollen, and their body releases histamine, causing them to sneeze. They take an antihistamine to block the histamine, which reduces their sneezing. However, if the person had a cold instead of an allergy, histamine would not be involved in causing their symptoms.

The question type is a Must Be True (MBT) question, which asks us to identify the statement that must be true based on the information provided in the passage.

Now let's discuss each answer choice:

a) Pollen and other allergens do not cause colds.

This answer choice is incorrect because the passage does not provide enough information to conclude that pollen and allergens do not cause colds. We only know that histamine does not play a role in how colds produce their symptoms, but allergens could still contribute to colds through other means.

b) Colds are more difficult to treat than allergies.

This answer choice is incorrect because the passage does not discuss the difficulty of treating colds versus allergies. This information is out of scope.

c) Antihistamines, when taken alone, are ineffective against congestion caused by colds.

This answer choice is tempting but incorrect. While the passage states that histamine does not play a role in how colds produce their symptoms, it does not definitively conclude that antihistamines are ineffective against congestion caused by colds. Antihistamines have other effects besides blocking histamine, and one of these other effects might help with congestion caused by colds.

d) The sleeplessness that sometimes accompanies allergies can be effectively treated with antihistamines.

This answer choice is incorrect because the passage does not mention sleeplessness as a symptom of allergies. Additionally, while antihistamines cause drowsiness, we cannot conclude that they effectively treat sleeplessness.

e) Any effect antihistamines may have in reducing cold symptoms does not result from blocking the action of histamine.

This answer choice is correct and must be true based on the passage. Since histamine does not play a role in how colds produce their symptoms, if antihistamines were to have any effect on reducing cold symptoms, it would not be due to blocking histamine's action. Instead, it would be due to one of the other effects of antihistamines.

In conclusion, the correct answer is E, as it must be true based on the information provided in the passage.