题目

  Children laugh often and easily . But as we grow up , we laugh less and feel more stressed. Try laughing for no reason at all . That’s how thousands of people start their day at Laughter Clubs around the world , and doctors now think that having a good laugh may be one of the best ways to stay healthy. The first Laughter Club was started in Mumbai ,India ,in  June,1995 by Dr Madam Kataria. “ Young children laugh about 300 times a day. Adults laugh between 7 and 15 times a day , ”says Dr Kataria . “Everyone’s naturally good at laughing . We want people to feel happy with t下列物质中，既能与盐酸反应又能与氢氧化钠溶液反应的是A.（NH4）2SO4B.Al（OH）3C.Na2SO4D.Mg（NO3）2