LSAT Explanation PT 32, S1, Q18: Until 1985 all commercial airlines completely

LSAT Question Stem

Which one of the following is most strongly supported by the information above? 

Logical Reasoning Question Type

This is a Most Strongly supported question. 

Correct Answer

The correct answer to this question is E. 

LSAT Question Complete Explanation

Let's first analyze the passage. It tells us that until 1985, commercial airlines replenished cabin air once every 30 minutes, and since then, it has been once every hour. The passage also states that the less frequently cabin air is replenished, the higher the level of carbon dioxide and the easier it is for airborne illnesses to spread. The question type here is Most Strongly Supported (MSS), which means we need to find the answer choice that is best supported by the information in the passage.

Now, let's discuss the answer choices:

a) This answer choice talks about a loosening of regulations concerning cabin air in commercial airline flights in 1985. However, the passage does not mention any regulations. It only informs us about the change in the rate of cabin air replenishment. Therefore, this choice is not supported by the passage.

b) This answer choice suggests that people who fly today are more likely to contract airborne illnesses than those who flew prior to 1985. While the passage does mention that less frequent cabin air replenishment makes it easier for airborne illnesses to spread, it does not account for other factors that could affect the likelihood of contracting illnesses. For example, there could be new measures in place to prevent sick people from boarding airplanes. So, this choice relies on unwarranted assumptions and is not strongly supported by the passage.

c) This answer choice states that low levels of carbon dioxide in cabin air make it impossible for airborne illnesses to spread. The passage does not provide enough information to support this extreme claim. It only tells us that less frequent cabin air replenishment leads to higher carbon dioxide levels and easier spread of airborne illnesses. So, this choice is not supported by the passage.

d) This answer choice claims that the rate of cabin air replenishment in 1980 was sufficient to protect passengers from the effects of carbon dioxide buildup. The passage does not provide enough information to determine whether the 1980 rate was sufficient or not. It only tells us about the change in the rate of cabin air replenishment and its effects on carbon dioxide levels and airborne illness spread. Therefore, this choice is not supported by the passage.

e) This answer choice states that the level of carbon dioxide in the cabin air on a two-hour commercial airline flight in 1980 was lower than it is today on a similar flight. This choice is supported by the passage, which tells us that the less frequently cabin air is replenished, the higher the level of carbon dioxide. Since the rate of cabin air replenishment was higher in 1980 (once every 30 minutes) compared to today (once every hour), it's reasonable to infer that the level of carbon dioxide on a similar flight in 1980 would be lower than today. So, this choice is the correct answer.

In conclusion, answer choice E is the most strongly supported by the information given in the passage.