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- Sat Jun 03, 2017 1:08 pm
#35679
Complete Question Explanation
(See the complete passage discussion here: lsat/viewtopic.php?t=14347)
The correct answer choice is (C)
Since this is a Main Point question, you should attempt to formulate a prephrase before beginning
to assess the answer choices. The main point of this passage, roughly, is to examine two discoveries
that led scientists to speculate that the geology of the ocean floor has changed over time.
Answer choice (A): The theories refined in the 1950s had little to do with the process by which the
ocean floor was formed many millions of years ago. On the contrary—they demonstrate that the
ocean floor is a “work in progress” that has changed over time. This answer choice is incorrect.
Answer choice (B): The discovery of the magnetic properties of basalt is not what helped scientists
account for the magnetic striping on the ocean floor. Basalt had long been known to be magnetic
(lines 7-11). What explains the striping on the ocean floor is the process of ocean floor spreading
described in the third paragraph. This answer choice is incorrect.
Answer choice (C): This is the correct answer choice. It is consistent with our prephrase, and is
directly supported by the discussion at the beginning of the passage (lines 1-4).
Answer choice (D): The process of ocean floor spreading may help explain the local distortions to
compass readings, but only if we take into account the peculiar magnetic properties of the basalt. In
any case, this answer choice fails to capture the main point of the passage and is therefore incorrect.
Answer choice (E): There is no evidence suggesting that the ocean floor’s magnetic variations
convinced scientists to map the entire ocean floor. This answer choice is incorrect.
(See the complete passage discussion here: lsat/viewtopic.php?t=14347)
The correct answer choice is (C)
Since this is a Main Point question, you should attempt to formulate a prephrase before beginning
to assess the answer choices. The main point of this passage, roughly, is to examine two discoveries
that led scientists to speculate that the geology of the ocean floor has changed over time.
Answer choice (A): The theories refined in the 1950s had little to do with the process by which the
ocean floor was formed many millions of years ago. On the contrary—they demonstrate that the
ocean floor is a “work in progress” that has changed over time. This answer choice is incorrect.
Answer choice (B): The discovery of the magnetic properties of basalt is not what helped scientists
account for the magnetic striping on the ocean floor. Basalt had long been known to be magnetic
(lines 7-11). What explains the striping on the ocean floor is the process of ocean floor spreading
described in the third paragraph. This answer choice is incorrect.
Answer choice (C): This is the correct answer choice. It is consistent with our prephrase, and is
directly supported by the discussion at the beginning of the passage (lines 1-4).
Answer choice (D): The process of ocean floor spreading may help explain the local distortions to
compass readings, but only if we take into account the peculiar magnetic properties of the basalt. In
any case, this answer choice fails to capture the main point of the passage and is therefore incorrect.
Answer choice (E): There is no evidence suggesting that the ocean floor’s magnetic variations
convinced scientists to map the entire ocean floor. This answer choice is incorrect.