In a series of experiments, hershey and chase radioactively labeled dna and protein in viruses and then used labeled viruses to infect bacteria. hershey and chase's experiments definitively showed that
a. dna and not protein is the genetic material.
b. protein and not dna is the genetic material.
c. neither dna nor protein act as a cell's genetic material.
d. dna and protein work together as a cell's genetic material.

A. DNA and not protein is the genetic material.

Explanation:

Hershey and Chase's experiment proved that DNA is the genetic material. In their experiment with radiolabelled protein coat of phage, the infected bacterial did not exhibit any radioactivity. This proved that the protein coat of the phage does not enter the bacterial cell to cause the infection and is not the genetic material  

On the other hand, the infected bacteria exhibited radioactivity when DNA of phage of radiolabelled. This proved that DNA was the genetic material since the DNA of the phage entered the bacteria, not the protein.  

meteorologists would compare a new weather map with one 24 h old to see how fast a front is moving.