DNA fingerprinting involves identifying differences in some specific regions in DNA sequence, called as :

The correct option is Repetitive DNA.

Step-by-Step Explanation:
DNA fingerprinting is a molecular biology technique used to identify and compare individuals based on the unique patterns present in their DNA. The methodology relies on analyzing specific regions of the genome that show high variability among different people.

1. What is Repetitive DNA?
A significant portion of the human genome consists of non-coding sequences that do not translate into proteins. Within these regions, a small stretch of DNA sequence is repeated many times. These specific regions are called repetitive DNA.

2. Significance in DNA Fingerprinting:
Because these repetitive sequences are non-coding, they accumulate mutations over generations without affecting an individual's survival. This leads to a high degree of genetic variation, known as polymorphism, in the length and number of repeats among different individuals. Since every person (with the exception of identical twins) possesses a unique pattern of these repetitions, identifying the differences in repetitive DNA regions allows scientists to construct a distinct genetic profile or "fingerprint" for an individual.

3. Understanding the Options:
• Repetitive DNA: The broad, primary class of DNA sequences where a small stretch of DNA is repeated multiple times, which is specifically targeted in DNA fingerprinting.
• Satellite DNA: A sub-category of repetitive DNA that separates as a distinct fraction during density gradient centrifugation. While it is analyzed during fingerprinting, "repetitive DNA" is the parent group of sequences referred to in standard definitions.
• Single nucleotides: Variations in single nucleotides (SNPs) exist, but classic DNA fingerprinting specifically focuses on the length variations of repeated segments.
• Polymorphic DNA: Polymorphism describes the state of genetic variation itself rather than the physical region of the DNA sequence.