Complete Question Explanation
Assumption—SN. The correct answer choice is (D)
This is very straightforward assumption question. In this type of question, you are given a statement
and an illogical response to that statement. Remember, however, that LSAT individuals are never
intentionally illogical; that is, their reasoning always seems sound to them, so there must be some
presumed condition or statement which would have logically led to the customer’s response. The task
here is to determine which of the answer choices best describes that misunderstood statement.
In this scenario, the shipping coordinator presents the customer with two options for shipment: air
express or ground carrier. The following conditions are expressed:
A (Air express) T (arrives tomorrow)
G (Ground carrier) T or T (does not arrive tomorrow)
The customer mistakenly interprets the first condition as:
That is, if the shipment is to arrive tomorrow, then it must be shipped by air express. This is commonly
referred to as a Mistaken Reversal, where the relationship between the Sufficient condition and the
Necessary condition is reversed. Answer choice (D) correctly expresses this misinterpretation. For this
question, the expense of each option is irrelevant.
Answer choice (A): Reliability is not an issue, as the customer mistakenly assumes that the only way
that the shipment can arrive tomorrow is to ship it with Air Express.
Answer choice (B): This is a correct interpretation of the shipping coordinator’s first statement
(essentially a restatement) and does not explain the customer’s response. Again, the customer mistakenly
reverses the relationship between shipping via Air Express and receiving the package the following day.
Answer choice (C): This is a correct interpretation of the shipping coordinator’s third statement, and the
latter half of the customer’s response clearly indicates that she understands this point.
Answer choice (D): This is the correct answer choice. Answer choice D is a very close paraphrase of
the customer’s expressed rationale. This answer choice can be diagrammed as:
Answer choice (E): This is the most attractive incorrect answer choice (although still chosen quite
infrequently by test takers). Though the customer is clearly aware of the increased cost of the air express,
this is not the critical factor in her response. The critical factor is her belief that air express is the only
way to get the package tomorrow.