Which one of the following statement is correct?

Consider the following four statements $\left(\mathrm{a}-\mathrm{d}\right)$ regarding kidney transplants and select the two correct ones out of these.

(a) Even if a kidney transplant is proper the recipient may need to take immunosuppressants for a long time.

(b) The cell-mediated immune response is responsible for graft rejection.

(c) The $\mathrm{B}$-lymphocytes are responsible for the rejection of the graft.

(d) The acceptance or rejection of a kidney transplant depends on specific interferons.

The two correct statements are: