The size of VNTR varies from:

The correct answer is Option (1) → 0.1 to 20 kb

VNTR (variable number of tandem repeats) is a short DNA sequence repeated many times one after another. The number of repeats differs from person to person, which is why it is used in DNA fingerprinting.

Option (1) 0.1 to 20 kb — Correct. VNTRs (variable number tandem repeats) are a class of mini-satellites. Their copy number varies from person to person, so their size varies from 0.1 to 20 kb.

Option (2) 0.2 to 10 bp — Incorrect. A few base pairs would be far too short; the range is in kilobases.

Option (3) 0.1 to 10 kb — Incorrect. The upper limit is 20 kb, not 10 kb.

Option (4) 0.2 to 20 kb — Incorrect. The lower limit is 0.1 kb, not 0.2 kb.

Note: The same question was also asked in CUET (UG) 2024 on 29-05-2024 (Slot 1).

NCERT Extract:
DNA Fingerprinting – “… The VNTR belongs to a class of satellite DNA referred to as mini-satellite. A small DNA sequence is arranged tandemly in many copy numbers. The copy number varies from chromosome to chromosome in an individual. The numbers of repeat show very high degree of polymorphism. As a result the size of VNTR varies in size from 0.1 to 20 kb.”