[单选题]
Four fixed charged point particles are atwjvo 1ilv1w:5hg1 d.g thesyy5os:xh72*a5c/w yf9psb cg)kfr ; 0r+l c x vertices of a rectangle. Which arrow 5s7w y2) s;y+g :*rcfc9l/xak05hrb scpxofyrepresents the net electric field at the center of the rectangle?
