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.

第一题我好像没在文章中找到两者的对比呀 只是说了vertical的是single group，这种细节题只能从文章中仔细找嘛？希望张老师回答一下

这个题A和C怎么选出来呢 希望唐老师回答一下

提问唐瑭老师，469这道题我选的c，做题思路：首先看问题是问DP改进了一个关于mon的什么事情？然后原文定位到红框里，最后对比选项，现在感觉D也有点对，请问下老师思路哪里出现了问题？

求问解题思路

求问解题思路

老师我算完得4，求问出错在哪里？（右图为解题过程）

提问这道题解题方法

老师提问这道题解题方法

求问解题思路

求问解题思路