While adding A and 8, we are getting 3 which shows that a number whose ones digit is 3.

But, this is only possible when digit A is 5.

In that case, the addition of A and 8 will give 13

And, 1 will be the carry for the next step.

Now,

In the next step,

1 + 4 + 9 = 14

Therefore, the addition is as follows:

Clearly, B and C are 4 and 1 respectively

Hence, A, B, and C are 5, 4, and 1 respectively