Software quality assurance is now an emerging sub - discipline of (36) . As Buckly and oston point out, (37) software quality assurance is likely to lead to an ultimate (38) of software costs. However, the major hurdle in the path of software management in this area is the lack of usable software (39) . The development of accepted and generally applicable standards should be one of the principal goals of (40) in software engineering.

A．balance

B．increment

C．production

D．reduction

热水采暖系统入口装置的结构形式可分为（）。

A．设调压截止阀的入口装置

B．设节流阀的入口装置

C．设调压板的入口装置

D．设混水器的入口装置