The correct option is C A radioactively labelled single stranded DNA molecule
The first step to making a genetic fingerprint requires getting a sample of DNA. The restriction enzymes are used to cut the DNA into smaller pieces. These fragments are called restriction fragments length polymorphisms, or RFLPs. These RFLPs are then put into an agarose gel. When the current of the electric field is turned on, the negative RFLPs will start to move across the gel towards the positive end. The smaller fragments move farther across the gel than the larger ones. Also, alkali is responsible for causing the hydrogen bonds to break, and the DNA to become single-stranded. When the DNA becomes single-stranded, it causes nucleotides to become free, and they will later be used to pair up with probes.