Correct Answer: A
Explanation:
From statement I:
A two digit number, greater than 9 and multiple of 51 should be 51 itself.
Because, 2 x 51 = 102 (3 digit number).
Therefore, I alone sufficient to answer.
From statement II:
A two digit number, greater than 9 and sum of the digit is 6.
It can be 15, 24, 33, 42, 51, 60.
So we cannot determine the required answer from the statement II alone.
Thus, I alone give the answer while II alone not sufficient to answer.