If \(A=\{x\in\mathbb{N}:x\le 20,\ x\text{ is prime}\}\) and \(B=\{x\in\mathbb{N}:x\le 20,\ x\text{ is odd}\}\), what is \(A\setminus B\)?

\(\{2\}\)

The primes not exceeding 20 are \(\{2,3,5,7,11,13,17,19\}\). Set \(B\) contains the odd natural numbers, so all the odd primes are removed from \(A\). The only prime that is not odd is 2, because 2 is the unique even prime. Hence \(A\setminus B=\{2\}\), making option A correct.

This is a Class 10 Mathematics question. Chapter: Sets. Topic: Operations on Sets (Union, Intersection, Difference).