C. are parallel and run in opposite directions.
Explanation – Deoxyribonucleic acid (DNA) is double stranded molecule present inside the nucleus of the cell and has double helical symmetry. The two strands run or proceeds antiparallel to each other which means that one strand proceeds from 5' to 3' direction while the other strand proceeds from 3' to 5' direction.
It so happens because the nitrogenous base from one strand binds to its complimentary base pair of the other strand. Hydrogen bond is the bond that connects nitrogenous bases of two strands.