As used throughout the passage, the term "common" is closest in meaning to which of the following

A．Ordinary.

B．Shared.

C．Simple.

D．Popular.

房地产市场预测是制定开发经营计划和营销决策的基础，是改善企业经营管理，提高( )的重要手段。

A．企业知名度

B．经济效益

C．竞争力

D．工作效率