3. Let $A=\left[\begin{array}{ccc}a & 3 & 5 \\ 5 & -1 & 3 \\ 2 & 3 & -4\end{array}\right]$ and $B=\left[\begin{array}{ccc}b & 1 & 4 \\ 4 & c & 1 \\ -3 & 1 & d\end{array}\right]$. If the trace of $A$ is -4 and $A B=\left[\begin{array}{ccc}-1 & 0 & 17 \\ -3 & 10 & 25 \\ 28 & -8 & 3\end{array}\right]$ then $a+b+c+d=$
- A
7
- B
-1
- C
3
- D
1
✓ Correct answer: C
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