請教黃金閱讀Begging by Nestlings - 英檢

Paragraph 1：Many signals that animals make seem to impose on the signalers
costs that are overly damaging. ■ A classic example is noisy begging by nestling songbirds
when a parent returns to the nest with food. ■ These loud cheeps and peeps might give the
location of the nest away to a listening hawk or raccoon, resulting in the death of the
defenseless nestlings.■ In fact,when tapes of begging tree swallows were played at an artificial swallow nest
containing an egg,the egg in that “noisy” nest was taken or destroyed by predators before the
egg in a nearby quiet nest in 29 of 37 trials.■

13. Look at the four squares [■] that indicate where the following sentence
could be added to the passage.

The cheeping provides important information to the parent, but it could also
attract the attention of others
.
Where would the sentence best fit?

為什麼答案是2不是1?不是應該要提出一個學說然後舉例嗎?

還是有什麼可以判斷的依據?@@

THX

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