The Adjacency matrix of a directed graph $\text{G}$ is given below.
$\begin{array} {} & a & b & c & d & e & f & g & h & i \\ a & 0 & 1 & 0 & 0 & 0 & 0 & 1 & 0 & 0 \\ b & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ c & 1 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 \\ d & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 \\ e & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 0 & 1 \\ f & 0 & 1 & 0 & 0 & 0 & 0 & 1 & 0 & 0 \\ g & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ h & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 0 & 1 \\ i & 0 & 1 & 0 & 0 & 0 & 0 & 1 & 0 & 0 \end{array}$
Which of the following is a valid topological sort of $\text{G}$?
- $(c, h, a, d, e, f, i, g, b)$
- $(h, e, i, f, c, d, a, b, g)$
- $(h, c, a, e, f, d, i, g, b)$
- $(c, a, d, e, f, g, h, i, b)$