Ans. is 'd' i.e., For quantitative dectection of PCR materialVarious types of PCR1) Multiplex PCR:# To find out the deletion mutation in a patient DNA.# In this type of PCR, multiple pairs of oligonucleotide primer are synthesized to amplify the entire gene or selected region of the gene.# After this, agrose gel electrophoresis reveals any deletion mutation compared to normal gene product.2) Reverse transcriptase PCR:# In this type of PCR, RNA is the starting material on which the reverse transcriptase enzyme acts to convert it to the DNA which is subsequently used for PCR.# DNA polymerase derived from thermus thermophillus organism has got additional reverse transcriptase activity and hence is preferred for reverse transcriptase type of PCR.3) Real time PCR:# In this type of PCR, a fluorescent dye known as "SYBR Green is used to tag the primer, this helps in quantitative detection of PCR material.4) Invert PCR:# In this type of PCR, the flanking region of the DNA is converted to target region and target region is convered to flanking region.# This is done for those DNA fragments for which the sequence of outer flanking region for the construction of primer is not known.5) Nested PCR :# In this type of PCR, specificity of amplification is enhanced by using new set of primer in each phase of the PCR# New set of primer is complimentary to the template DNA sequence which is downstream to the first primer, i.e. nested between the original set of primer.