qns. what is EcoR1 ..???

can the answer be restriction enzyme...??? is it wrong...and why.???

Yes, EcoR1, is used as a restriction enzyme in various molecular biology techniques, such as cloning.  The restriction enzymes are also known as restriction endonulcease.This enzyme  is isolated from a bacterial strain, E.coli. It is used to produce sticky ends of DNA, before ligation in various techniques in molecular biology.