单选题 . ①Unlike herbivores and omnivores, predators have traditionally been thought not to balance nutrient intake because of the assumption that animal tissue as a food source varies little and is nutritionally balanced. ②But chemical analysis of invertebrate prey reveals remarkable variation in nutrient composition among species; even within species, nutrient composition may vary considerably. ③Greenstone suggested that predators may select food items according to their nutrient contents. ④Jensen et al (2011) have shown experimentally that even sit-and-wait invertebrate predators with limited mobility can work to address nutrient deficiencies. ⑤The wolf spider, for instance, has been shown to regulate nutrient intake by extracting more dry mass from a prey item if it contains a higher proportion of a nutrient that was deficient in the previous prey.

7. The passage supplies information for answering which of the following questions? ______

A、 Do invertebrate predators with full mobility address nutrient needs in the same fashion as sit-and-wait invertebrate predators with limited mobility?
B、 Why would there be a considerable variation in nutrient composition within prey of a given species?
C、 Is all of the nutrient content of invertebrate prey contained in the dry mass?
D、 What would a wolf spider do if a fly it was eating contained a higher proportion of a certain nutrient than was present in the spider's recent prey?
E、 How is a wolf spider able to determine that some prey it is eating contains a higher proportion of a nutrient that was deficient in the previous prey?

【正确答案】 D

【答案解析】 这种问答类的题目需要注意选项是一般疑问句还是特殊疑问句。如果是一般疑问句，那么根据文章能用yes或no回答的，都可以选。但如果是特殊疑问句，一定要根据原文得到具体的回答才能选。
D：正确，根据文章第⑤句话，狼蛛会从这只猎物中提取更多的干物质。
A：文章没提到predators with full mobility。
B：文章没有回答why的问题。
C：根据文章我们只知道干物质中有营养，但不知道是不是所有营养都在干物质里。
E：文章看不出狼蛛判断营养含量的具体方式。