To study the mechanism of dna replication, meselson and stahl labeled labeled both strands of a dna molecule with nitrogen-15 and then tracked the location of this label after one round of replication. Which composition describes the products they found? A. Both double helixes were composed of large segments of the original strands and large segments of new strands.
B. one double helix was composed of the two original strands, and the other was composed of two new strands
C. both double helixes were composed of small segments of the original strands and small segments of new strands.
D. both double helixes were composed of one original strand and one new strand

explanation would be great!