下列关于时间片轮转算法的叙述中，哪一个是不正确的( )

A．在时间片轮转算法中，系统将CPU的处理时间划分成一个个时间段
B．就绪队列中的各个进程轮流在CPU上运行，每次运行一个时间片
C．时间片结束时，运行进程自动CPU并进入等待队列
D．如果时间片长度很小，则调度程序抢占CPU的次数频繁，增加了系统开销

An analyst does research about measurement of financial assets. An appreciated marketable security carried at fair market value with unrealized gain or loss in comprehensive income is most likely classified as:（）

A. held for trading.

B. held to maturity.

C. available for sale.