Step-by-step explanation:
Kornberg performed the experiment to identify the molecules which could be able to replicate the DNA. He used a bacterial strain and bacteriophage which could infect the bacteria by incorporating its DNA.
He was able to detect an enzyme which cold assemble all the molecules to form a new DNA strand and named the enzyme as DNA polymerase.
This DNA polymerase can replicate biologically active DNA in which biologically active means that a biological active progeny DNA of phage was which is very accurate and is viable is produced by the bacteria using the enzyme DNA polymerase.