单项选择题
Software Engineering is best described as ( )。
A.the practice of designing, building, and maintaining off-the-shelf software from prefabricated parts
B.the practice of designing, building, and maintaining ad-hoc software without the use of formal methods
C.the practice of designing, building, and maintaining reliable and cost-effective software using standard techniques
D.the practice of designing, building, and maintaining fast and flexible software specifically for engineering applications