求助阅读题

hjy111UID: 3822601

What accounts for the low-lying, flat surface of Mars’s north? On Earth’s surface, higher- and
lower-lying areas have different types of crust: one, thin and dense, is pulled toward Earth’s center more strongly by gravity, and the planet’s water naturally comes to sit over it, creating oceans. The processes that generate this oceanic crust drive plate tectonics.
Is Mars’s north similarly characterized by a sort of crust different from other areas of the planet? Some researchers do see signs of tectonic activity surrounding the northern basin that suggest that it was created through the formation of new crust, like ocean basins on Earth. However, McGill points to Northern bedrock structures that predate the features said to mark the start of the tectonic process. McGill instead believes that through some novel mechanism the ancient surface sank to its current depth as a single unit. This would explain why features around the basin’s edge, which would have formed as the surface dropped, seem to be younger than structures at its floor. The third possibility is that the northern lowlands result from impacts. Some researchers suggest they formed as a series of big overlapping impact craters. Others arguing that the odds against such a pattern of impacts are large, postulate a single event-the impact of an object bigger than any asteroid the solar system now contains.

2. Which of the following can be inferred from the passage about geological features on Earth
A. the relative elevation of the lowest-lying regions of the crust arises in part from forces generated within the planet
B. the difference in elevation between the ocean basins and their surroundings is greater than the difference between Mars’s northern basin and its surroundings
C. the formation of low-lying areas proceeds by a different process than the one that created
Mars’s northern basin
D. the weight of the oceans does not affect the depth of the ocean basins
E. the proportions of the crust that is oceanic crust is increasing

我在A和C之间纠结了挺久，正确答案A,为什么C不对？

我Me是个好人UID: 3724812

A我认为是从这里infer出来的:
On Earth’s surface, higher- and lower-lying areas have different types of crust: one, thin and dense, is pulled toward Earth’s center more strongly by gravity, and the planet’s water naturally comes to sit over it, creating oceans. 其中different types对应relative; forces generated within the planet对应gravity.
C没看懂是什么意思...抱歉...

hjy111UID: 3822601

我Me是个好人 发表于 2017-7-23 01:59
A我认为是从这里infer出来的:
On Earth’s surface, higher- and lower-lying areas have different type ...

C 怎么会看不懂？就是说地球low lying area 的形成过程和火星northen basin的形成过程不一样，第二段第一个论点就是说这个的....但是我就是看不懂为啥C不对。

我Me是个好人UID: 3724812

hjy111 发表于 2017-7-23 02:17
C 怎么会看不懂？就是说地球low lying area 的形成过程和火星northen basin的形成过程不一样，第二段第 ...

好吧看懂了...
不吧, 这篇文章一共出现了三种possibilities, 第一种是由some researchers提出的, 他们的观点是similar: They do see signs of..., like ocean basins on Earth, 所以C就错了.
另外, 第二第三种都只是对这种现象的不同解释, 因而三种解释是并列关系, 而不是说谁驳斥了谁.

hjy111UID: 3822601

我Me是个好人 发表于 2017-7-23 02:45
好吧看懂了...
不吧, 这篇文章一共出现了三种possibilities, 第一种是由some researchers提出的, 他们 ...

好吧，有点道理。。我以为第二种观点否认了第一种观点，不过从题目和最后结果来看的确是并列的