Restriction enzymes recognize and cut:

a.

random DNA base-pair sequences

c.

single-stranded DNA

b.

double-stranded DNA

d.

RNA

double - stranded DNA

Explanation:

A restriction enzyme is a DNA-cutting enzyme that recognizes specific sites in DNA. Many restriction enzymes make staggered cuts at or near their recognition sites, producing ends with a single-stranded overhang. If two DNA molecules have matching ends, they can be joined by the enzyme DNA ligase