4. Why do you see only two colonies in panel C (film exposed to nitrocellulose treated with antibodies)? Choose between wrong and possible.
a. Most bacteria did not contain plasmids with cDNAs.
b. Only two colonies were formed by bacteria with plasmids containing cDNA encoding for Cancer Antigen 1.
c. Some colonies were lost during the transfer to nitrocellulose membranes.
d. Some of the colonies lost the plasmids during the lysis and so no Cancer Antigen 1 could  be detected.