What is the greatest prime factor of (2⁴)²-1?

A 3

B 5

C 11

D 17

Correct Answer: Option D

(2⁴) ²-1
=(2⁴+1)(2⁴-1) [a²-b²=(a+b)(a-b)]
=(16+1) (16-1)
=17×15
=17×5×3
So ,The greatest prime factor is 17