Correct option is C
Given:
356yx is divisible by 90
Concept used:
A number is divisible by 9 when the sum of digit of the number is divisible by 9.
Solution:
In number 356yx x=0 because number is divisible by 90.
According the divisible rule of 9.
3+5+6+y+0=18
y =18-14
y=4
So, value of y-x= 4-0 =4.