If 2257 is the result of subtracting 4577 from 7056 in base n, find n

A.
8 
B.
9 
C.
10 
D.
11
Correct Answer: Option A
Explanation
(begin{array}{cc} 7056 \ text{ 4577} \hline 2257 end{array})
By trial and error method
Let the base to 8
i.e. Let n = 8 and it is easily verified that the subtraction holds.
The subtraction does not hold when other values of n are tried
n = 8