問題詳情


(B) The milky pools, where these 1.5 cm-long fish live, stretch far back into the cave. They are slimy withunusual bacteria that require sulfur, not sunlight, to live. The fish have become central to an annual rite ofthe people of the area: They drop a poisonous plant into the waters just inside the cave, killing mollies thatflow out of the cave. They then collect and eat the fish in a fertility-related rite.Back in Hamburg, the scientists tested the preferences of the cave females in darkness by watching themin infrared light. The Atlantic mollies manifest their preferences by swimming longer near larger males andspending less time around smaller prospects. Scientists suspect the cave mollies are using a sensory organknown as the lateral line, a line of pores along the side that, like eardrums, can sense pressure changes, tofind the bigger males. While the cave females have had to evolve a novel way of detecting large mates, theyenjoy an edge in mating with the lights out. 
Researchers also describe how these zippy males never stop trying to mate with females. “Malesconstantly harass females. They are copulating. They do nothing but copulate and the females can’t feed.”But life in caves has calmed the molly males. The reason is probably that in the dark, oxygen-poor waters ofthe cave, simply finding a female is an energy-intensive task, making harassment on top of that too costly. 

25. Based on the passage, what do the two bold-sized “They” respectively refer to?
(A)the pools; the residents in that area
(B) the pools; the bacteria
(C) the Atlantic mollies; the bacteria
(D)the fish; people of that region

參考答案

答案：A
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)

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