Inside the computer, the operation system (of another software module called a data communication (71) )must decide which program will get control next. Each program remember, is associated (72) . a particular front -end port. If a program’s data have not yet reached its front - end buffer, there is no point giving that program control. Thus the data communication monitor sends its own (73) signal to the front -end devices next port is polled. Note that the (74) computer speed. The computer never has to wait for a terminal or a communication line. Instead, it is the expressive front - end processor that waits for the slower system (75) to respond.

（71）处填（）。

A.memory

B.control

C.monitor

D.charge

天花粉在复元活血汤中的作用是（）

A．润燥生津，清热化痰

B．清热润燥，散结消肿

C．理气宽胸，涤痰散结

D．清热化痰，理气宽胸

E．以上都不是