Thick PBS is made for:
Ans. is 'b' i.e., Prevalence of parasite (Ref: D.R. Arora, 3rd/e)* Thin PBF - For Speciation.* Thick PBF - For Prevalence and Presence of Malarial parasites.
Speciation
Prevalance of parasite
Both speciation and prevalence
None
Parasitology