Since the able person, John, is in ______ charge of the matter, we’re sure that the matter is under _____ control now.

A．the; the

B．the; /

C．/; the

D．/; /

数据库设计分为以下6个设计阶段：需求分析阶段、______、逻辑设计阶段、物理设计阶段、实施阶段、运行和维护阶段。