Q.
Alfred Hershey and Martha Chase made a big contribution in proving $DNA$ role as the hereditary molecule. The experiment is shown in the diagram. $A$ and $C$ are the presence or absence of radioactivity detected in cells $B$ and $D$ are the presence or absence of radioactivity detected in supernatant cells. Identify $A, B, C$ and $D$ -

Molecular Basis of Inheritance
Solution: