Hi All,

This is my first post, so if I make any major "faux pas", please let me know. This post is regarding a MSS question on PT Feb 1997, Section 3, Question 16.

In this question stimulus, we are given a discussion about zebra mussels—an invasive species in the Great Lakes that possesses some redeeming qualities. Zebra mussels consume algae that they filter from the water, and in discharge streams, they improve water quality by removing some amounts of hazardous waste.

Question stem: Which one of the following is most strongly supported on the basis of the statements above, if they are true?

Responses:

(A). Zebra mussels arrived on transatlantic freighters, and displace native species.

A is incorrect. This is because it is irrelevant how or why the Zebra mussels are here. We want to know what the implications of their redeeming qualities and presence in the lakes means for the chemical plant.

(B). If Zebra mussels spread to the Mississippi River, the clam industry will collapse.

B is incorrect. This response is irrelevant, we simply don't have any information in the passage to show that the Mississippi River clam industry will collapse. Also, we aren't really interested in this information either.

(C). There is no mechanical means of clearing the Zebra mussels.

C is incorrect. This response is irrelevant and is not supported by the passage. There very well could be mechanical means or other means of clearing the Zebra mussels.

After reviewing all of the answers, I was down to the final two responses:

(D). The algae on which the mussels feed would, if not consumed by the mussels, would clog the intake pipes at the chemical plants.

D This answer is incorrect. I anticipated that this statement is the most strongly supported. Based on my initial reading, it seemed like this would be a logical inference to make. The algae would likely clog the intake pipes, BUT FOR the zebra mussels consuming them.

Do we not have enough information from the passage to support this answer?

(E). Any hazardous waste the mussels remove from the chemical plant will remain in the mussels, if they do not transform it, they must be regarded as hazardous waste.

Answer (E) is the correct answer. This answer is the most strongly supported response. This answer is somewhat sensible, but it still seems a bit off. How do we know that the hazardous waste will go into the mussels? The last clause of the sentence makes sense "if they do not transform it, they (the mussels) must be regarded as hazardous waste". However, for this to be true, we must accept the first clause of the sentence, which I don't think we currently have enough support in the passage to make.

Note: This is the major curve-breaking response, and is likely a major source of error/frustration for many. I am one of the frustrated ones. In short, I am still a bit confused on why E is correct, rather than D. Answer E simply sounded a bit too a dystopian Sci-Fi of a response to be correct.

I would appreciate any feedback that you folks have to offer. Thanks.