单选题 Each instruction is processed (75) ，and several instructions are at varying stages of execution in the processor at any given time，this is called instruction pipelining．

【正确答案】 C
【答案解析】[解析] 每一条指令都是顺序处理的，在某个给定时刻，数条指令同时处在不同的执行阶段，这种执行方式称为指令的流水处理。