If a strand of DNA is - 3' GCTTAGTCCG 5';
the complementary strand would be - 5' CGAATCAGGC 3'
3' GCTTAGTCCG 5'; - strand
5' CGAATCAGGC 3' - complimentary strand
So there is no correct answer i guess. But if we change the polarity(change 3' to 5' and 5' to 3') of option B, then B would be the correct answer.