Who was the first scientist to use the term 'virus' as a pathogen of infectious diseases?

Which of the following plants can perform photosynthesis even at temperatures below $-20^{\circ}C$ / freezing point?

$A$ capsid is .........

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 $R$?

Potato leaf-roll disease is caused by

Lichens are indicators of $SO_2$ pollution because they are ........