The part of the virus which gives it the hereditary feature is

What is the genetic material of $TMV$?

Tobacco Mosaic Virus $(TMV)$ has:

Assertion $A$: Bacteriophages are bacteria-eating viruses.
Reason $R$: Bacterial viruses are obligate parasites in bacterial cells.
Which option is correct for Assertion $A$ and Reason $R$?

The bacteriophage which infects colon bacterium is:

What do viroids represent?