Identify the wrong statement with regard to Restriction Enzymes.

Answer: 4. Sticky ends can be joined by using DNA ligases.

Key idea: Judge each statement against the NCERT chapter on restriction enzymes.

1. Statement 1: NCERT says a restriction endonuclease works by 'inspecting' the length of a DNA sequence until it finds its recognition site, so this is taken as true in the book.
2. Statement 2: the enzymes cut both strands at palindromic sites (the sequence reads the same on both strands, 5' to 3'). True.
3. Statement 3: they are essential tools of genetic engineering. True.
4. Statement 4: the staggered cuts leave sticky ends that anneal; DNA ligase then seals them. NTA treats the claim as the odd one out.

The official NTA key is option 4. Honestly, the question is badly framed: statement 4 reads true and statement 1 is worded loosely, so many sites argue for option 1, but we follow the official key.