A loop, made of straight edges has six corner at A(0, 0, 0), B(L, 0, 0), C(L, L, O), D(O, L,O), E(O, L, L) and F (0, 0, L). A magnetic field $B = B_o(\hat{i} + \hat{k})T$ is present in the region.
The flux passing through the loop ABCDEFA (in that order) is
$(a)B_oL^2Wb$
$(b)2B_oL^2Wb$
$(c)\sqrt 2B_oL^2Wb$
$(d)4B_oL^2Wb$