OFFICIAL EXPLANATION
Jane drinks 4 cups of coffee every day. Thus, Jane must have trouble sleeping at night.
The above conclusion relies on which of the following assumptions?A. Jane drinks the last cup of coffee at 21:00.
Incorrect.
The fact Jane drinks coffee at night may serve as another premise supporting the conclusion. However, it is not the author's assumption, i.e., it does not explain why the author concluded drinking four cups every day means Jane must have sleeping problems.
To solve this question, first make sure you read the Question stem correctly. You are looking for the assumption made by the author - what the author must have assumed to get to the conclusion.
Next, read the Argument and map it: Jane drinks 4 cups of coffee every day is the premise, the data; Jane must have trouble sleeping at night is the author's conclusion.
Now Think of the answer: the assumption should link drinking 4 cups of coffee a day to having trouble sleeping at night. How did the argument's author get from drinking 4 cups of coffee every day to the conclusion that Jane must have trouble sleeping at night?
The answer is that they must be causally linked. That is, that one is the cause of the other. Now Look for an answer choice that fits that idea. Before you choose it, Scan the other answer choices just to be sure.B. Jane goes to bed at 22:00.
Incorrect.
The fact Jane goes to bed at 22:00 is meaningless to the argument (be careful not to combine it with answer choice A!). It does not explain why the author concluded drinking four cups every day means Jane must have sleeping problems.C. Jane also drinks 4 cups of tea every day.
Incorrect.
The fact Jane drinks four cups of tea a day as well may serve as another premise supporting the conclusion. However, it is not the author's assumption, i.e., it does not explain why the author concluded drinking four cups of coffee every day means Jane must have sleeping problems.D. Coffee causes sleep problems.
This is the author's assumption - it explains why the author concluded drinking four cups every day means Jane must have sleeping problems.E. If Jane drinks tea, she sleeps a lot better.
Incorrect.
The fact Jane finds tea conducive to her sleep is meaningless to the argument. It does not explain why the author concluded drinking four cups every day means Jane must have sleeping problems.
To solve this question, first make sure you read the Question stem correctly. You are looking for the assumption made by the author - what the author must have assumed to get to the conclusion.
Next, read the Argument and map it: Jane drinks 4 cups of coffee every day is the premise, the data; Jane must have trouble sleeping at night is the author's conclusion.
Now Think of the answer: the assumption should link drinking 4 cups of coffee a day to having trouble sleeping at night. How did the argument's author get from drinking 4 cups of coffee every day to the conclusion that Jane must have trouble sleeping at night?
The answer is that they must be causally linked. That is, that one is the cause of the other. Now Look for an answer choice that fits that idea. Before you choose it, Scan the other answer choices just to be sure.