单项选择题

A.划线→锯割→锉削→钻孔→倒角→折弯
B.划线→折弯→钻孔→倒角→锯割→锉削
C.划线→钻孔→倒角→折弯→锉削→锯割
D.划线→锉削→折弯→锯割→钻孔→倒角