题目

阅读理解Therewas once a lonely girl who longed so much for love. One day while she was walkingin the woods she found two starving songbirds. She took them home and put them ina small cage, caring them with love. Luckily, the birds grew strong little by little.Every morning they greeted her with a wonderful song. The girl felt great love forthe birds. One day the girl left the door to the cage open accidentally. The larger and stronger of the two birds flew from the cage. The girl was so frightened that he would fly away. So as he flew close, she grasped him wildly. Her heart felt glad at h下列叙述正确的是（ ）A．固体氯化钠不导电，所以氯化钠不是电解质B．氢氧化钠水溶液能导电，所以氢氧化钠是电解质C．三氧化硫溶于水能导电，所以三氧化硫是电解质D．硫酸、纯碱、小苏打和生石灰分别属于酸、碱、盐和氧化物