Assume that you are trying to insert a gene into a plasmid.Someone gives you a preparation of genomic DNA that has been cut with restriction enzyme X.The gene you wish to insert has sites on both ends for cutting by restriction enzyme Y.You have a plasmid with a single site for Y,but not for X.Your strategy should be to

A)insert the fragments cut with restriction enzyme X directly into the plasmid without cutting the plasmid.
B)cut the plasmid with restriction enzyme X and insert the fragments cut with restriction enzyme Y into the plasmid.
C)cut the DNA again with restriction enzyme Y and insert these fragments into the plasmid cut with the same enzyme.
D)cut the plasmid twice with restriction enzyme Y and ligate the two fragments onto the ends of the DNA fragments cut with restriction enzyme X.
E)cut the plasmid with restriction enzyme X and then insert the gene into the plasmid.