OG No.16 Quesion 105 help

Australian researchers have discovered electroreceptors
(sensory organs designed to respond to electrical fields)
clustered at the tip of the spiny anteater’s snout. The
researchers made this discovery by exposing small areas of
(5) the snout to extremely weak electrical fields and recording
the transmission of resulting nervous activity to the brain.
While it is true that tactile receptors, another kind of
sensory organ on the anteater’s snout, can also respond to
electrical stimuli, such receptors do so only in response to
( 10) electrical field strengths about 1,000 times greater than
those known to excite electroreceptors.
Having discovered the electroreceptors, researchers are
now investigating how anteaters utilize such a sophisticated
sensory system. In one behavioral experiment, researchers
(15) successfully trained an anteater to distinguish between
two troughs of water, one with a weak electrical field
and the other with none. Such evidence is consistent with
researchers’ hypothesis that anteaters use electroreceptors
to detect electrical signals given off by prey; however,
( 20) researchers as yet have been unable to detect electrical
signals emanating from termite mounds, where the favorite
food of anteaters live. Still, researchers have observed
anteaters breaking into a nest of ants at an oblique angle
and quickly locating nesting chambers. This ability quickly
(25)to locate unseen prey suggests, according to the researchers, that the anteaters were using their electroreceptors
to locate the nesting chambers.

105. The passage suggests that the researchers mentioned in
the second paragraph who observed anteaters break into
a nest of ants would most likely agree with which of the
following statements?
(A) The event they observed provides conclusive
evidence that anteaters use their electroreceptors to
locate unseen prey.
(B) The event they observed was atypical and may not
reflect the usual hunting practices of anteaters.
(C) It is likely that the anteaters located the ants’ nesting
chambers without the assistance of electroreceptors.
(D) Anteaters possess a very simple sensory system for
use in locating prey.
(E) The speed with which the anteaters located their
prey is greater than what might be expected on the
basis of chance

i chose A,but the key is E,i could hardly agree with the explanation offered in OG,ask for help,thanks a lot

Such evidence is consistent with
researchers’ hypothesis that anteaters use electroreceptors
to detect electrical signals given off by prey; however,
( 20) researchers as yet have been unable to detect electrical
signals emanating from termite mounds, where the favorite
food of anteaters live.

A is wrong because this evidence is not conclusive.

pls repeat choice E agian, you will know what realy it means

on the basis of chance alone. 这什么意思？基于偶然性的基础上？

The speed with which the anteaters located their prey is greater than what might be expected on the basis of chance