题目

When I was eight, I had to cross a crime-filled neighborhood to school. Nobody got involved when there was a__41    ,not even if a killing was happening directly across from our  42  :What's that, Mom? Someone is screaming！Turn off the light！ Stay  43  I Keep your voice down! Mom would    44  .     Usually,1 would see other girls that I knew, and I would catch up and we would  45 together.     Along this route was an old grey house with a    46  .  It never caught my attention   47    a kind and lovely elderly lady    48    us with a musical voice 下列区分两种不同物质的方法不合理 的是（　　）A．用燃着的木条区分空气与氮气B．用肥皂水区分硬水与软水C．用酚酞试液区分氢氧化钾溶液与盐酸D．用水区分CuO粉末与MnO2粉末