To reduce the danger to life and property posed by majorearthquakes, scientists have been investigating several techniques for givingadvance warning of dangerous earthquakes. Since catfish swim erratically before earthquakes, some investigatorshave proposed monitoring catfish to predict dangerous earthquakes.

　　Which of the following, if true, most seriouslyundermines the usefulness of the proposal?

　　(A) In Japan, which is subject to frequent earthquakes,the behavior of catfish has long been associated with earthquakes.

　　(B) Mechanical methods for detecting earthquakes have notproved effective.

　　(C) Tremors lead to the release of hydrogen sulfide gasinto water, thereby causing various fish and shellfish to behave erratically.

　　(D) Careful construction can reduce the dangers posed byearthquakes.

　　(E) Even very slight, fleeting tremors cause catfish toswim erratically.

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