Final answer:
The Watson and Crick model for DNA replication suggests that it is semiconservative, where each DNA molecule after replication consists of one parental strand and one new strand.
Step-by-step explanation:
The Watson and Crick model states that DNA replication is semiconservative. This means that when DNA replicates, each of the two original strands, or parental strands, serves as a template for a new, complementary strand. After replication, each new DNA molecule consists of one old parental strand and one newly synthesized strand. This was confirmed by the Meselson and Stahl experiment, which supported the semiconservative model over the conservative and dispersive models. In conservative replication, both parental strands would remain together after replication, and in dispersive replication, each DNA molecule would have interspersed segments of old and new DNA.