In $1920$,nucleic acid was identified as a major component of which of the following?

The present concept of central dogma in retrovirus is given by . . . . . . in $1970$.

How many of the following organisms have $RNA$ as their genetic material?
$TMV$,Humans,Bacteria,$Q\beta$ bacteriophage,Bacteriophage $\lambda$,Yeast,Maize,$\phi \times 174$ bacteriophage,Retroviruses.

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?

$DNA$ is the genetic material was proved by ...... .

During the course of evolution,why was $DNA$ chosen over $RNA$ as the genetic material? Provide reasons by first discussing the desired criteria for a molecule to act as genetic material and by analyzing the biochemical differences between $DNA$ and $RNA$.