Finding pattern (2,7,8,3,5)

Question

What would replace $Z$ in the following sequencing? $$\begin{matrix} 2 & 3 & 4 \\ 7 & 6 & 5 \\ 8 & 7 & 1 \\ 3 & 0 & Z \\ 5 & 4 & 3 \\ \end{matrix}$$ $a)\ 1$

$b)\ 2$

$c)\ 4$

$d)\ 7$

Note. I've added my answer below. If you have another way to solve this question, I would be happy to read that.

Answer 1

Sum of the entries in first column is $2+7+8+3+5=25$. And that of second column $=3+6+7+0+4=20$

So, sum of entries of third column is $15=4+5+1+Z+3\implies Z=2$.

Answer 2

(2+7+3+8)/4=5; (3+6+7+0)/4=4; (4+5+1+z)/4=3, so z=2.