Hind II is a restriction endonuclease which always cut DNA molecule at a particular point by recognizing:

Specific sequence of six base pairs

The correct answer is Option (3) → Specific sequence of six base pairs 

Restriction Endonucleases (Molecular Scissors): Restriction enzymes belong to a larger class of enzymes called nucleases. These are enzymes that are commonly referred to as "molecular scissors" because they cut DNA molecules at specific recognition sequences. These recognition sequences are often palindromic, meaning the sequence reads the same forwards and backward.

Restriction enzymes belong to a larger class of enzymes called nucleases. These are of two kinds; exonucleases and endonucleases. Exonucleases remove nucleotides from the ends of the DNA whereas, endonucleases make cuts at specific positions within the DNA.

The first restriction endonuclease–Hind II, whose functioning depended on a specific DNA nucleotide sequence was isolated and characterized five years later. It was found that Hind II always cut DNA molecules at a particular point by recognizing a specific sequence of six base pairs. This specific base sequence is known as the recognition sequence for Hind II.