From the choices given below mark the co-prime numbers      (a)   2, 3(b)   2, 4(c)   2, 6(d)   2, 110

The co-prime numbers are those pairs of numbers that have only 1 as their common factor.

(a) 2, 3: The factors of 2 are 1 and 2. The factors of 3 are 1 and 3. The only common factor is 1. So, 2 and 3 are co-prime numbers.

(b) 2, 4: The factors of 2 are 1 and 2. The factors of 4 are 1, 2, and 4. The common factors are 1 and 2. So, 2 and 4 are not co-prime numbers.

(c) 2, 6: The factors of 2 are 1 and 2. The factors of 6 are 1, 2, 3, and 6. The common factors are 1 and 2. So, 2 and 6 are not co-prime numbers.

(d) 2, 110: The factors of 2 are 1 and 2. The factors of 110 are 1, 2, 5, 10, 11, 22, 55, and 110. The common factors are 1 and 2. So, 2 and 110 are not co-prime numbers.

Therefore, the co-prime numbers from the given choices are 2 and 3.