The correct option is B A=8, B=7, C=4
The sum of numbers in any row or column or diagonal of the magic square is the same.
We have second column completely filled.
So, the magic sum = 1 + 5 + 9 = 15
It means the numbers in each row or column or diagonal sum up to 15.
In the first row we have,
A+1+6 = 15
So, A = 8
In the second row we have,
3+5+B = 15
So, B = 7
In the third row we have,
C+9+2 = 15
So, C = 4.