We ______ here two hours ago. We ______ here for two hours. [ ]

A. have arrived, have been

B. have come, have been

C. came, have come

D. arrived, have been

某村在网上开办的“村民博客”不仅方便了村民直接参与村务管理，而且创新了农村基层管理模式。“村民博客”有助于村民[ ]

A．行使国家权利

B．行使民主权利

C．行使选举权

D．履行政治性义务