Consider the following pseudocode for depth-first search (DFS) algorithm which takes a directed graph $G(V, E)$ as input, where $d[v]$ and $f[v]$ are the discovery time and finishing time, respectively, of the vertex $v \in V$. Suppose that the input directed graph $G(V, E)$ is a directed acyclic graph (DAG). For an edge $(u, v) \in E$, which of the following options will NEVER be correct?

Consider the following pseudocode for depth-first search (DFS) algorithm which takes a directed graph G(V, E) as input, where d[v] and f[v] are the discovery time and finishing time, respectively, of the vertex v V. Suppose that the input directed graph G(V, E) is a directed acyclic graph (DAG). For an edge (u, v) E, which of the following options will NEVER be correct?

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