According to Friedrich Miescher,what type of substance is 'nuclein'?

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?

The result of which of the following reaction experiments carried out by Avery et al. on $Streptococcus \text{ } pneumoniae$ has proved conclusively that $DNA$ is the genetic material?

Transforming principle in bacteria is $DNA$. This was first proved through experiments performed by . . . . . . .

Give an account of the Hershey and Chase experiment. What did it conclusively prove? If both $DNA$ and proteins contained phosphorus and sulphur,do you think the result would have been the same?