From six candidates interviewed, only two qualify for the principal position, while all six are eligible for the vice-principal roles. If one principal and two vice-principals need to be chosen, how many different selection combinations are possible?

Explanation

The total number of ways to select one principal from the two eligible candidates is 2C1 = 2. After choosing the principal, five candidates remain eligible for the two vice-principal posts. The number of ways to select two vice-principals from these five is 5C2 = 10. Therefore, the total number of combinations is 2 x 10 = 20, which does not match any of the given options A, B, or C. Hence, the correct choice is 'None of the above'.