Which of the following methods are commonly used in DNA finger printing?

PCR & RFLP

The correct answer is Option (2) -PCR & RFLP

DNA fingerprinting involves identifying differences in some specific regions in DNA sequence called as repetitive DNA, because in these sequences, a small stretch of DNA is repeated many times. These repetitive DNA are separated from bulk genomic DNA as different peaks during density gradient centrifugation. The bulk DNA forms a major peak and the other small peaks are referred to as satellite DNA. Since DNA from every tissue (such as blood, hair-follicle, skin, bone, saliva, sperm etc.), from an individual show the same degree of polymorphism, they become very useful identification tool in forensic applications. Further, as the polymorphisms are inheritable from parents to children, DNA fingerprinting is the basis of paternity testing, in case of disputes. The technique of DNA Fingerprinting was initially developed by Alec Jeffreys. He used a satellite DNA as probe that shows very high degree of polymorphism.

Two commonly used methods in DNA fingerprinting are:

PCR can be used in DNA fingerprinting to generate numerous copies of isolated DNA, selectively amplifying a single copy of a desired sequence.

Restriction fragment length polymorphism (RFLP) refers to differences (or variations) among people in their DNA sequences at sites recognized by restriction enzymes. Such variation results in different sized (or length) DNA fragments produced by digesting the DNA with a restriction enzyme. RFLPs can be used as genetic markers, which are often used to follow the inheritance of DNA through families. RFLP is used in forensic analysis.