The correct option is C 108
Concept: When a number is mutiplied by any other counting number, the obtained product result is called multiple of the number.
On multiplying 9 with 12 we get 108.
Hence, 108 is a multiple of 9 &12.
9 is multiple of 3 & 6 but 3 & 6 are factors of 9 not multiples of 9.
And, 343 is not completely divisible by 9, So it is not the multiple of 9.