Critical Reasoning

Sharks have a higher ratio of cartilage mass to body mass than any other organism. They also have a greater resistance to cancer than any other organism. Shark cartilage contains a substance that inhibits tumor growth by stopping the development of a new blood network. In the past 20 years, none of the responses among terminal cancer patients to various therapeutic measures has been more positive than the response among those who consumed shark cartilage. If the claims made above are true, then each of the following could be true EXCEPT:

(A) No organism resists cancer better than sharks do, but some resist cancer as well as sharks.
(B) The organism most susceptible to cancer has a higher percentage of cartilage than some organisms that are less susceptible to cancer.
(C) The substance in shark cartilage that inhibits tumor growth is found in most organisms.
(D) In the past 20 years many terminal cancer patients have improved dramatically following many sorts of therapy
(E) Some organisms have immune systems more efficient than a shark's immune system.

Hi Atul,

GMAT CR question stems don't ask you "...each of the following could be true EXCEPT." That's staple on the LSAT not the GMAT.

Anyways, "could be true EXCEPT?" means the four wrong answer could be true, making the right answer something that must be false.

(If you don't want an answer and explanation of the answer, then don't read the following.)

[spoiler]Because the second sentence of the passage tells us that sharks have a greater resistance to cancer than any other organism, the second clause of choice A must be false ("...but some resist cancer as well as sharks"). So, choice A is correct and there is absolutely no need to look at the other answer choices.[/spoiler]