Give scientific reasons: In recombinant $DNA$ technology,the use of endonuclease is more proper than exonuclease.

(N/A) In recombinant $DNA$ technology,the fragment of desired $DNA$ must be joined with a vector or amplified. For this,precise cutting of both the vector and the desired $DNA$ is essential.
Endonucleases cut $DNA$ at specific internal sites,often producing 'sticky' or cohesive ends.
Exonucleases remove nucleotides from the ends of $DNA$ molecules,typically resulting in 'blunt' ends.
Sticky ends are necessary for the efficient annealing and ligation of the desired $DNA$ fragment into the vector.
Therefore,endonucleases are more suitable than exonucleases for recombinant $DNA$ technology.