$PCR$ technique was invented by

The most thoroughly studied of the known bacteria-plant interactions is the

Most suitable method of introducing alien $DNA$ into a plant cell is

About gene gun method:
$I.$ This method is also known as biolistic technique.
$II.$ In this method,cells are bombarded with high-velocity micro-particles of gold or tungsten coated with $DNA$ in plants.
$III.$ Important crop plants like maize,rice,and wheat have now been transformed by this method.
Which of the statements given above are correct?

Today,we know more than $...$ restriction enzymes that have been isolated from over $...$ strains of bacteria.

$A$ set of bacterial clones,each containing a plasmid or phage,is called