Select the correct option for the $R$ strain of bacteria.

When did Frederick Griffith conduct a series of experiments using bacteria?

Following representations $P$,$Q$ and $R$ denote few steps of the Griffith Experiment. Identify the correct one$(s)$:
$P. R$ strain $\rightarrow$ Inject into mice $\rightarrow$ Mice die
$Q. S$ strain (Heat killed) $\rightarrow$ Inject into mice $\rightarrow$ Mice die
$R. R$ strain $\rightarrow$ Inject into mice $\rightarrow$ Mice live

Which scientist experimentally proved that $DNA$ is the sole genetic material in bacteriophage?

Who revealed the biochemical nature of the transforming principle? How was it done?

Transformation in bacteria was discovered by