Statement I: Restriction endonucleases do recognise unique sequences to cut the DNA. These sequences are arranged in the form of a palindrome.
So, statement I is correct.
Statement II: Restriction endonucleases cut the DNA strand a little away from the centre of the palindromic site. This helps generate sticky ends.
So, statement II is correct.
Option 4 is correct.
Note: Statement II is correct as per NCERT but is not correct scientifically as a general statement for restriction endonucleases.