then value of x and y are equal to –

Correct option is C

We see in second column 7 becomes 6 when 1 is borrowed by 6 in column 1.
Now we see that when a number is subtracted from 6 gives the same number which is to be 3.
Thus, we get y = 3
In 3rd column we see that x – 6 = 3
Thus, we get x = 9
9976 – x639 = 3337