GMAT Question of the Day

November 10, 2009

Every weekday, GMAT Hacks publishes a realistic GMAT practice question. In general, you'll see Quant problems on Monday, Wednesday, and Friday, and Verbal questions on Tuesday and Thursday. You'll always be able to find them at

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Today's Practice GMAT Question:

Commensalism is any relationship between two living things in which one benefits and the other is neither helped nor harmed. Oxpecker birds are commensal species that flock with the large mammals of the African Savannah. They feed on ticks, fleas, and flies that are attracted to the mammals' fur.
Which of the following, if true, can most reasonably be inferred from the statements above?
(A) Oxpecker birds are neither helped nor harmed by the large mammals of the African Savannah.
(B) Ticks, fleas, and flies are commensal species in their relationship with both oxpecker birds and the large mammals of the African Savannah.
(C) No species exist in a commensal relationship with oxpecker birds except for large mammals of the African Savannah.
(D) In commensal relationships, the smaller of the species in the relationship usually benefits while the larger is neither helped nor harmed.
(E) Preying on small creatures drawn to the fur of the large mammals of the African Savannah does not significantly affect those mammals.


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Need more work in this area? In Total GMAT Verbal, there is an entire chapter, including practice problems, that covers Inference.

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About the author: Jeff Sackmann is a GMAT tutor based in New York City. He has created many resources for GMAT preparation, including the popular Total GMAT Math and Total GMAT Verbal, as well as 1,800 practice GMAT math questions.

Total GMAT Verbal

The comprehensive guide to the GMAT Verbal section. Recognize, dissect, and master every question type you'll face on the test. Everything you need, all in one place, including 100+ realistic practice questions.
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