这题是啥意思，我一点都看不懂，牛牛们帮帮忙！

A scrub jay can remember when it cached a particular piece of food in a particular place, researchers have discovered, and tend not to bother to recover a perishable treat if stored long enough to have rotted.

1. tend not to bother to recover a perishable treat if

2. they tend not to bother recovering a perishable treat
3. tending not to bother to recover a perishable treat it
4. tends not to bother recovering a perishable treat
5. tends not bothering to recover a perishable treat it

答案是D