这道题正确答案是 B， 我一直觉得是D, 不是特别明白 B 答案为什么 说as effectively as sea snakes can? One such adaptation is the closer proximity of the terrestrial snake's heart to its head, which helps to ensure circulation to the brain, regardless of the snake's orientation in space. The heart of sea snakes can be located near the middle of the body, a position that minimizes the work entailed in circulating blood to both extremities. In arboreal snakes, however, which dwell in trees and often assume a vertical posture, the average distance from the heart to the head can be as little as 15 percent of overall body length. Such a location requires that blood circulated to the tail of the snake travel a greater distance back to the heart, a problem solved by another adaptation. 20. It can be inferred from the passage that which of the following is true of species of terrestrial snakes that often need to assume a vertical posture? (A) They are more likely to be susceptible to circulatory failure in vertical postures than are sea snakes. (B) Their hearts are less likely to be located at the midpoint of their bodies than is the case with sea snakes. (c) they cannot counteract the pooling of blood in lower regions of their bodies as effectively as sea snakes can. (d) the blood pressure at their midpoint decreases significantly when they are titled with their heads up.

不知道自己判断标准是否对 前三相似，对比前三，按逻辑rules只能被intend，with intent、intending是主动，（实际做时，B我不知with intent是主动，我根据后面不是从句而是短语所以判断不如A）；对比DE，D我觉得should不好，E的this指代不清。

DE读起来可以选对是E，但说不出为啥。

原文不长，读一下意思，看到than肯定要和前面并列形式一致，认为individuals是说某个物种，于是后面应该是别的物种。（按正确答案来，individuals应该是指基因的某几个组成部分？？？）

请问老师，这题选C？？？不是用答案带入直接选出B吗？17og的数学题，麻烦啦

请问这个第一句怎么翻译，what是引导的什么从句？

Paleontologist Stephen Jay Gould has argued that many biological traits are not the products of natural selection, favored due to their enhancement of reproduction or survival, but that they are simply random by-products of other evolutionary developments. (A) due to their enhancement of reproduction or survival, but that they are (B) due to the reproduction or survival they enhance, but they are (C) because they enhance reproduction or survival, but (D) because they enhance reproduction or survival, but are (E) because of enhancing reproduction or survival, but are

数学，余数问题如何求通项公式？

for example、such as、include、contain、like的区别