During western blotting, the primary antibody recognizes:
a. the secondary antibody
b. mrna
c. chromosomal dna
d. the protein of interest

The correct answer will be option-D.

Explanation:

Western blotting is a technique used to separate and identify the protein from a mixture of samples.  

The protein is separated on the basis of its molecular weight which is done by running the sample on gel electrophoresis. The separated protein is then transferred to a membrane which produces a band of the protein sequence. These protein bands membrane is then incubated with the specific antibodies for the protein. The antibodies will bind to the protein and unbound antibody is washed off. The bound antibodies are seen easily by developing a film.

Thus, option-D is the correct answer.

a and c are the answeres