可以对冲击矿压的危险程度按冲击矿压危险状态等级评定的综合指数法定量化地分为（）级

A.五

B.三

C.二

D.四

(66) method is the use of a data processing system to represent selected behavioral (67) of a physical or abstract system. For example, the representation of air streams around airfoils at various velocities, temperatures, and air pressures with such a system.

Emulation method is slightly different, it uses a data processing system to imitate another data processing system, so that the imitating system accepts the same data, executes the same programs, and achieves the same (68) as the imitated system. Emulation is usually achieved (69) hardware or firmware. In a network, for example, microcomputers might emulate terminals (70) communicate with mainframe.

（70）处填（）。

A．in order to

B．for

C．therefore

D．to this end