单项选择题

已知298K时,φθ(Ag+,Ag)=0.799V,下列电池的Eθ为0.627V .Pt, H2│H2SO4(aq)│Ag2SO4(s)│Ag(s) 则 Ag2SO4的活度积为:()

A.3.8×10-17
B.1.2×10-3
C.2.98×10-3
D.1.52×10-6