Hind II always cuts DNA molecules at a particular point called recognition sequence and it consists of:

The correct answer is option (1). The first restriction endonuclease - Hind II, whose functioning depends on a specific DNA nucleotide sequence was isolated. It was found that Hind II always cut DNA molecules at a particular point by recognising sequence of six base pairs. Option (2), (3) and (4) are incorrect because they have either more than 6 or less than 6 bp.