________ of the two story books are very interesting, so I can't decide which one to choose. [ ]

A. All

B. Any

C. Either

D. Both

一个独家垄断厂商，具有很大的垄断权利，所以( )

A．可以通过提价增加销售收入和利润

B．如果降价，必定会减少销售收入和利润

C．要固定价格才能使销售收入和利润最大

D．以上三种说法都错误