---- _____ do you play football?

----  Once a week.

A．How long

B．How soon

C．How often

D．How

为进一步诊治下列哪项检查最有价值

A．膀胱镜检查

B．尿路平片和排泄性尿路造影

C．血尿常规，肝、肾功能

D．膀胱造影