题目

There are lots of stories about long lives of animals.Some people say snakes can live for hundreds of years.Some say birds can sleep for years.After they wake up，they are living！These stories are very interesting for us to read. But do you think they are true(真实的)？No！Most animals don't live as long as people do.Of course，it's hard to know an animal's age.Because animals can't say，“I'm...years old.” But here are some animals. An elephant is very old at 60.A horse is old at 50.Bears can live to be about 35.Monkeys can live to be 25.The oldest birds are parrots and ab＞0，则①|a+b|＞|a|②|a+b|＜|b|③|a+b|＜|a-b|④|a+b|＞|a-b|四个式中正确的是（　　）A．①②B．②③C．①④D．②④