题目

It’s difficult for doctors to help a person with a hurt brain.  36  enough blood, the brain can live only three to five minutes. Usually doctors can’t fix the hurt  37  such a short time.Dr Robert White thinks he knows a  38  of help. He thinks doctors should make the hurt brain  39  to live for 30 minutes without blood. This gives the doctor  40  time to do something for the brain. Dr White experimented his  41  on fifteen monkeys.  42  he taught them to do different jobs. Then he operated on them. He made the monkeys’ blood go  43  a machine. When the brains’  44  w有关物质的用途错误的是（　　）A．稀盐酸可用于除去铁锈B．一氧化碳可用来冶炼金属C．熟石灰可治疗胃酸过多D．稀有气体制成多种用途的电光源