求助！T-3-Q14

veralove3271

A scrub jay can rememberwhen it cached a particular piece of food in a particular place, researchershave discovered, and tend not to bother to recover a perishable treat ifstored long enough to have rotted.
A.    tend not to bother to recover a perishable treat if
B.    they tend not to bother recovering a perishable treat
C.    tending not to bother to recover a perishable treat it
D.    tends not to bother recoveringa perishable treat      (D)
E.    tends not bothering to recover a perishable treat it


我想问researchers have discovered在这里做什么？是和 can remember，tends not to一起平行么？感觉在这里莫名其妙，还是我没读懂？

chaseconsult

can remember 和tends not to平行
a scrub jay can remember ....and a scrub jay tends not

veralove3271

researchers have discovered不是一个有主谓宾的完整句子么，那既不是平行，前半句话里怎么出现了can和have discovered两个谓语呢？不懂额~~