The Value of the Beta-Galactosidase Gene in Cloning Could Best

The value of the beta-galactosidase gene in cloning could best be described as the gene:

A) that provides valuable restriction enzyme cut sites.
B) that "reports" if a recombinant product is formed.
C) that confers resistance to antibiotics.
D) that facilitates easier transfer of the DNA into bacterial cells.
E) that encodes a special DNA ligase enzyme.