Which restriction endonuclease was the first to be discovered?

Restriction endonuclease enzymes are used to:

$A$ specific recognition sequence identified by endonucleases to make cuts at specific positions within the $DNA$ is:

$A$ : $DNA$ ligase plays an important role in recombinant $DNA$ technology.
$R$ : The linking of antibiotic resistance gene with plasmid vector became possible by enzyme $DNA$ ligase.

Which restriction site is present in the $amp^R$ gene in $pBR322$?

The first restriction endonuclease was isolated from which of the following?