The structure of a virus,which is covered by a protective protein coat,is known as...

What was the contribution of the scientist $T$. $O$. Diener in $1971$?

Which of the following causes the potato spindle tuber disease?

Which of the following is considered an acellular organism?

$S :$ The symbiotic association between algal and fungal components is called lichen.
$R :$ The study of lichens is called lichenology.

Assertion $A$: Viroids and viruses can pass through bacteria-proof filters.
Reason $R$: Bacteria are retained by bacteria-proof filters.
Which option is correct for Assertion $A$ and Reason $R$?