The correct option is D 7
For a number to be divisible by 9, the sum of its digits should be divisible by 9.
Hence for 20x to be divisible by 9, the value of 2 + 0 + x should be divisible by 9.
Then, 2 + x should be divisible by 9.
The smallest multiple of 9 which is greater than 2 is 9 itself.
⇒ x = 7
Therefore the smallest value of x for which the number 20x is divisible by 9 is 7.
Verification:
As we obtained the value of x as 7, the number is 207.
Sum of its digits = 2 + 0 + 7 = 9.
9 is divisible by 9.
Therefore, 207 is divisible by 9.
(2079=23)