Bunuel
In the spring of 1778, the Continental Army installed a “great chain” across the Hudson River, at West Point,
in order to prevent British ships to navigate into the vulnerable regions to the north.
(A) in order to prevent British ships to navigate into
(B) by preventing British ships from navigating into
(C) so that they prevented British ships to navigate to
(D) to prevent British ships from navigating to
(E) by means of preventing British ships from navigating to
Magoosh Official Explanation
Split #1: idiom. The verb “prevent” idiomatically takes the preposition “from.” Choices (A) & (C) make the mistake of following “prevent” with an infinitive phrase, which is idiomatically incorrect. We can reject those two choices.
Split #2: navigating “to” vs. “into” the northern regions. The choice of “into” is a little unusual, but it’s not incorrect. We cannot reject anything on the basis of this split.
Split #3: cause vs. consequence. The remaining choices present logical difficulties. Consider the two actions:
(1) installing the “great chain” across the Hudson
(2) preventing the ships from navigating
What causes what? Which is the cause and which is the purpose? Clearly, (1) is the cause, the purpose of doing (1) is to accomplish (2); in other words, (2) is the goal. Thus, using an infinitive of purpose for (2) would be appropriate, and that’s exactly what (D) does. Both (B) & (E) suggest that (2) is the cause or means, and that (1) is the purpose or result, and this does not make sense. Both of those are incorrect.
Choice (D) is the only possible answer.