How did the Hershey-Chase experiments use radioactive labeling to demonstrate that DNA is the genetic material of viruses?

• A. By labeling DNA and protein with different radioactive isotopes and showing only DNA entered bacterial cells.
• B. By labeling carbohydrates and proteins and showing carbohydrates were not genetic material.
• C. By labeling lipids and proteins and showing lipids were not involved in genetic transfer.
• D. By labeling RNA and protein and showing RNA was the genetic material.

Answer: (A)