A2. In a magic square, the three row sums, the three column sums, and the two diagonal sums are equal to each other. (A row sum is the sum of the numbers in a row, etc.) For the $3 \times 3$ magic square depicted here, three numbers have been filled in.

Which number must be placed in the position of the question mark?
A) 2
B) 4
C) 6
D) 8
E) 9

![](https://cdn.mathpix.com/cropped/2024_04_17_17b311164fb12c8a5afcg-1.jpg?height=303&width=309&top_left_y=1670&top_left_x=1596)
A2. B) $4 \quad$ See figure. From $F+10+3=F+D+7$ it follows that $D=6$. From $7+E+3=C+D+E=C+6+E$ it follows that $C=7+3-6=4$.