Answer:
The feature of DNA replication that makes it semi-conservative is the creation of new DNA strands from old DNA strands.
Step-by-step explanation:
DNA replication occurs semi-conservatively because it is from two old DNA strands that the new DNA strands will emerge. Each new strand is complementary to the old strand, so the genetic code is retained in the new DNA molecules. Replication is initiated from single sources and usually occurs bi-directionally from each replication source. Replication fidelity is very high, with an average of only one error per billion nucleotides incorporated after error synthesis and correction during and immediately after replication.