题目

Everyone looks forward to progress, whether in one's personal life or in the general society. Progress indicates a person's ability to change the way he is living at the moment. Progress must lead a better way of doing things. All these, however, remains true only in so far as people want to accept technology and move forward by finding new and more efficient ways of doing things. However, at the back of the minds of many people, especially those who miss the “good old days”, efficiency comes with a price. When communication becomes efficient, people are able to contact one another 下列各组物质中，全部是由离子构成的一组物质是A. H2SO4、NaOH、CaO B. KNO3、H2O2、C60C. Al2O3、液氨、NaHCO3 D. 火碱、NH4HCO3、KMnO4