Which of the following is not a Pythagorean triplet

Which of the following is not a Pythagorean triplet

Which of the following is not a Pythagorean triplet?

(a) (3, 4, 5)

(b) (7, 24, 25)

(c) (11, 60, 61)

(d) (9, 41, 42)

Answer: D