Which of the following radioisotopes is not suitable for $DNA$ labeling-based studies?

Recall the experiments done by Frederick Griffith,Avery,MacLeod,and McCarty,where $DNA$ was speculated to be the genetic material. If $RNA$,instead of $DNA$,was the genetic material,would the heat-killed strain of $Pneumococcus$ have transformed the $R$-strain into a virulent strain? Explain.

What happens if a live $S$ strain of Streptococcus pneumoniae is injected into a mouse?

Which of the following is the genetic material?

How did Hershey and Chase differentiate between $DNA$ and protein in their experiment while proving that $DNA$ is the genetic material?

$A :$ DNase can inhibit the process of transformation.
$R :$ Transformation is the absorption of a $DNA$ segment from the surrounding medium by a living bacterium.