请教36套上的一道阅读题

smqpfUID: 3132364

Exercise24,第3篇,第4题

Because of its accuracy in outlining the Earth's subsurface, the seismic-reflection method remains the most important tool in the search for petroleum reserves. In field practice, a subsurface is mapped by line arranging a series of wave-train sources, such as small dynamite explosions, in a grid pattern. As each source is activated, it generates a wave train that moves downward at a speed determined uniquely by the rock's elastic characteristics. As rock interfaces are crossed, the elastic characteristics encountered generally change abruptly, which causes part of the energy to be reflected back to the surface, where it is recorded by seismic instruments. The seismic records must be processed to correct for positional differences between the source and the receiver, for unrelated wave trains, and for multiple reflections from the rock interfaces. Then the data acquired at each of the specific source locations are combined to generate a physical profile of the subsurface, which can eventually be used to select targets for drilling.

4. According to the passage, in the seismic-reflection method which of the following have a significant effect on the signal detected by the seismic instruments.
A presence of unrelated wave trains
B placement of the seismic instruments;
C properties of rocks through which the wave train has traveled

这题的答案是ABC

我想问一下,文中有提到The seismic records must be processed to correct for positional differences between the source and the receiver, for unrelated wave trains, and for multiple reflections from the rock interfaces. 也就是说A和B的影响会被修正,那么AB应该就不会有significant effect啊...所以我想知道为何要选AB...
求解答...

leijerry888UID: 3143968

我觉得潜在的意思是 They must be processed to correct because they have significant effects on the signal.
题目中问的也是，哪个选项中的东西会有影响，并没有问这个影响是否需要修正。

smqpfUID: 3132364

2# leijerry888 感谢楼上的回答...
然后,0.0...我对于ETS的逻辑产生了很诡异的感觉...
因为我看这到题没有写infer,所以我就感觉correct之后就没有影响了,所以没有选AB,伤不起...
也就是说,文中即使是说了有修正,但其潜在逻辑就是有影响是么...
好诡异的敢脚,哎...