分类法在化学学科的发展中起到了非常重要的作用，下列分类标准合理的是
| A．根据是否具有丁达尔效应，将分散系分为溶液、浊液和胶体 |
| B．根据反应中是否有电子转移，将化学反应分为氧化还原反应和非氧化还原反应 |
| C．根据水溶液是否能够导电，将物质分为电解质和非电解质 |
| D．根据是否含氧元素，将物质分为氧化剂和还原剂 |
Jenny nearly missed the flight______ doing too much shopping.
| A．as a result of | B．on top of | C．in front of | D．in need of |
The CDs are on sale! Buy one and you get ______ completely free.
| A．other | B．others | C．one | D．ones ks |
I’m sure that your letter will get______ attention. They know you’re waiting for the reply. 
| A．continued | B．immediate | C．careful | D．general |
All the dishes in this menu, ______ otherwise stated, will serve two to three people. 
| A．as | B．if | C．though | D．unless |
The children loved their day trip, and they enjoyed the horse ride ______.
| A．most | B．more | C．less | D．little |