The complementary nature of the double-stranded DNA shows that it follows specific base-pairing principles: A pairs with T, and G pairs with C. This would have particular effects on gene expression. The immediate effect of this complementarity is that the partner strands can never be identical with one another.
Since the two strands of the DNA molecule are complementary, for any given gene:
A. The RNA polymerase can bind to either strand.
B. Only one strand actually carries the genetic code for a particular gene.
C. Each gene possesses an exact replica that can be used should a mutation occur.
D. A gene transcribed in the 5' to 3' direction on one strand can be transcribed in the 3' to 5' direction on the other strand.