I asked him to come at seven o’clock, but he __________. It’s already eight o’clock．

A．didn’t show off

B．didn’t show up

C．hasn’t shown up

D．hasn’t shown off

下列哪项是错误的( )

A．抗-HAVIgM阳性可诊断为HAV近期感染

B．HBsAg和HDAg均呈阳性，可诊断为HBV及HDV联合感染

C．单项抗-HBc阳性时，可诊断为HBV现症感染

D．HCV-RNA阳性时可诊断为HCV现症感染

E．抗-HEVIgM阳性可诊断为HEV近期感染