The correct option is C 36
The smallest number divisible by both 9 and 12 is the smallest common multiple of 9 and 12.
Multiples of 9: 9, 18, 27, 36, 45, 54, 63...
Multiples of 12: 12, 24, 36, 48, 60...
From the list of multiples of 9 and 12, we can see that 36 is the least common multiple of 9 and 12.
So, 36 is the smallest number divisible by both 9 and 12.