Official Explanation(1) Take a First Glance (5 seconds)
The initial split between the (noun) and that of the (noun) often indicates that the sentence is testing Comparisons. Keep that in mind as you read the sentence, and make sure that it’s logical to compare whatever is being compared.
(2) Read for Meaning
The phrase less painful than confirms that the sentence is comparing two things. The original sentence compares the tarantula hawk wasp’s sting to the bullet ant itself. It should compare the stings of the two insects; comparing a sting to an insect is illogical. Eliminate answer (A).
The original sentence contains a second Meaning error: it says that the sting lasts for five minutes, but the sting itself occurs in a moment. The sentence should say that the pain caused by the sting lasts for five minutes.
(3) Find a Starting Point
Start with any difference that seems easiest to you, then move to the next easiest issue, and so on. Stop when you have one answer or you aren’t sure how to address the remaining differences. All errors for each choice are detailed in the next section.
(4) Eliminate (and Repeat)
(A) This sentence illogically compares the tarantula hawk wasp’s sting to the bullet ant itself. It should compare the stings of the two insects. In addition, it says that the sting lasts for five minutes, but the sting itself occurs in a moment.
(B) CORRECT. This answer fixes the broken comparison by correctly comparing the stings of the two insects. It also correctly conveys that the pain, rather than the sting, lasts for five minutes.
(C) This answer fixes the broken comparison by correctly comparing the stings of the two insects. However, the opening modifier although it … humans incorrectly modifies the tarantula hawk wasp’s sting. This implies that it is the tarantula hawk wasp’s sting whose sting is less painful than the bullet ant’s, but the sting itself doesn’t have a sting! Further, the second part of this construction indicates that the tarantula hawk wasp’s sting is what rarely bothers humans. In fact, it is the tarantula hawk wasp itself that rarely bothers humans.
(D) This answer fixes the broken comparison by correctly comparing the stings of the two insects. However, it has a meaning error that is quite subtle. Compare this answer with choice (B); there are two differences. Both lasts only five minutes and lasts for only five minutes are correct idioms—that split is a red herring. The only remaining difference is the beginning of each split: that of the aptly-named bullet ant vs. the aptly-named bullet ant’s. Each of these structures makes a correct comparison, but the second structure introduces a meaning error: the aptly-named bullet ant’s (sting) indicates that it is the bullet ant’s sting that is aptly-named. In fact, it is the bullet ant itself that is aptly-named; the sting does not have a name.
(E) The phrase the aptly-named bullet ant’s introduces a meaning error, incorrectly implying that it is the bullet ant’s sting that is aptly-named. In fact, it is the bullet ant itself that is aptly-named; the sting does not have a name. This answer also contains a modifier error. To determine what the opening modifier although … humans modifies, mentally ignore the subsequent modifier when … sting. What follows the comma is the pain, but the pain neither has a sting, nor rarely bothers humans. Rather, it is the tarantula hawk wasp that has a sting less painful than the bullet ant’s sting and that rarely bothers humans.