请问：PP3 review-CR(part1)-4

不好意思，没找到这道题在OG里面对应的相应题号，请帮我看一下：

Fact1: Television advertising is becoming less effective: the proportion of brand names promoted on television that viewers of the advertising can recall is slowly decreasing.

Fact2: Television viewers recall commercials aired first or last in a cluster of consecutive commercials far better than they recall commercials aired somewhere in the middle.

Fact2 would be most likely to contribute to an explanation of fact 1 if which of the floowing were also true?

(A) The average television viewer currently recalls fewer than half the brand names promoted in commercials he or she saw.

(B) The total time allotted to the average cluster of consecutive television commercials is decreasing.

(C) The average number of hours per day that people speand watching television is decreasing.

(D) The average number of clusters of consecutive commercials per hour of teleci\\vision is increasing.

(E) The average number of television commercials in a cluster of consecutive commercials is increasing.

答案是E。我用排除法可以选出，可是其中的逻辑关系有些糊涂，请帮我讲解一下好吗？

万分感谢~~~bow~~~ ^____^

谢谢！cluster of consecutive commercials原来是这个意思~~