<prompt> Viral plaque is made in lab for -Quantitative assay of infectivity of virusDiagnosis of virusQualitative assay of infectivity of virusType of virus  <response>: Quantitative assays measure the actual number of infectious paicles in the inoculum includes 2 methods-plaque assay and pock assay. REF:ANATHANARAYAN AND PANIKERS TEXTBOOK OF MICROBIOLOGY 8TH EDITION PAGE NO:437 