单项选择题

已知反应2HgC12(aq)+Sn2+(aq)↔Sn4+(aq)+Hg2C12(s)+2Cl-(aq)的EΘMF=0.5032V,EΘ(Sn4+/Sn2+)=0.1539V,则EΘ(HgC12/Hg2C12)=()

A.0.3493V
B.0.3286V
C.1.314V
D.0.657lV