Lots of wild animals often do babysitting duty. Young female elephants who haven't had babies yet like to help guide and take care of baby elephants.

Recently, a team of researchers at the Southwest Forestry University in China noticed that during the breeding (繁殖) season, black-and-white snub-nosed monkeys passed around their babies a lot. The monkeys would take turns to carry or even feed the newborns.

This behaviour reminded the team of the way humans babysit for each other. So they decided to watch the monkeys more closely. They followed the group for six months and recorded more than 400 scenes in which a female monkey interacted (互动) with a mother and newborn or gently pulled them closer.

Once the newborns had grown up a bit, the mothers would allow other females to take care of them. They made their decision according to who has the most parenting experience. After a more experienced monkey had given up her babysitting duty, the younger females with less experience would still be allowed to look after the babies.

Cui Chunyan, one of the researchers in the study, mentioned that this helps the younger females to learn more about parenting to prepare them for having their own babies in the future. She also said that more research needs to be done to find out if mothers make their choices based on the social status of other monkeys or on whether they are related to each other.

1.1. What have the researchers noticed in the study?

A Monkeys babysit others' babies.

B Monkeys are too busy to babysit.

C Elephants would take babysitting duty.

D Elephants would guide baby elephants.

解析：选A。A 细节理解题 文章第一段以大象为例引入动物界普遍的“babysitting”现象，第二段指出研究团队最近的发现：“black-and-white snub-nosed monkeys passed around their babies a lot. The monkeys would take turns to carry or even feed the newborns.” 这直接说明猴子会照顾其他猴子的宝宝。A选项准确概括了这一核心发现。

2.2. How did the researchers study the monkeys?

A By interacting with mother monkeys.

B By watching them from time to time.

C By recording and studying their behaviours.

D By looking after the mother and baby monkeys.

解析：选C。C 细节理解题 根据文章第三段“They followed the group for six months and recorded more than 400 scenes...”可知，研究人员是通过长期跟踪观察并记录猴群的行为来进行研究的。C选项“通过记录和研究它们的行为”最准确。A、D选项是干预行为，不符合文意；B选项“不时观看”不够精确。

3.3. Which of the following can be a perfect babysitter?

A A monkey that has no children.

B A monkey that cares for its parents.

C A female monkey with rich parenting experience.

D A female monkey with less parenting experience.

解析：选C。C 细节理解题 根据文章第四段“They made their decision according to who has the most parenting experience.”可知，猴妈妈在选择保姆时，依据的是“最多的育儿经验”。因此，经验丰富的雌性猴子是完美的保姆人选。C选项与此完全一致。

4.4. What can we learn from Cui Chunyan's words in the last paragraph?

A They will continue their research.

B They are satisfied with the results.

C They have found out monkeys' social status.

D They have completely understood monkeys' babysitting choices.

解析：选A。A 推理判断题 文章最后一段引用了研究员崔春燕的话，她在解释当前研究发现（帮助年轻雌性学习育儿）后，明确指出“more research needs to be done”来探究更深层次的选择依据。这表明他们的研究尚未结束，还将继续。A选项符合此推断。

5.5. What can we find out from the study of monkeys' babysitting choices?

A Monkeys like human behaviours.

B People should protect the monkeys.

C Researchers compared elephants with monkeys.

D Younger monkeys will be better mothers by caring for babies.

解析：选D。D 推理判断题 本题询问从对猴子选择保姆的研究中我们可以发现什么。文章的核心发现之一是，年轻雌性猴子通过照顾宝宝来学习育儿技能，为将来成为母亲做准备。这直接对应D选项的含义。A、B、C选项要么是过度推断，要么偏离了研究的主要发现。