Graph Traversals

Step 1: DFS Applications.
- **Topological Sort**: DFS is used to generate a topological ordering of vertices in a Directed Acyclic Graph (DAG).

- **Determining Strongly Connected Components (SCCs)**: DFS can be used in algorithms like Kosaraju's algorithm to identify strongly connected components in a graph.

- **Solving Maze Problem**: DFS is often applied to explore a maze by visiting each possible path and backtracking when necessary.

Step 2: Incorrect Application.
- **Finding minimum distance to a node in an unweighted graph optimally**: This task is usually solved using **Breadth-First Search (BFS)**, not DFS. BFS explores the graph level by level, ensuring the shortest path in an unweighted graph.

Step 3: Conclusion.
The correct answer is **(3) Finding minimum distance to a node in an unweighted graph optimally**.