Answer: Manifest content coding
Step-by-step explanation:
Manifest content coding contains explicit rules for coding and as little dependency on interpretation by researcher.It keeps content's data as it is in the coding mechanism.
According to the question,Perlman is using manifest content coding as he is coding the actual number of lines of gender reference in book which will depict explicit method of coding .He is not dependent on interpreting .
Other options are incorrect because latent content coding, theoretical sampling and quota sampling are not done by Perlman .Thus, the correct option is manifest content coding.