A* algorithm is based on a. Breadth-First-Search b. Best-First-Search c. Depth-First-Search d. Bulkworld Problem.

Analyzing the Question

To determine the basis of the A* algorithm, we need to understand its core concepts and what it is designed to optimize.

Relevant Concepts

The A* algorithm is a pathfinding and graph traversal algorithm. It is used for finding the shortest path from a start node to a goal node. The algorithm combines features of both Dijkstra's algorithm and Greedy Best-First Search.

Analysis and Detail

1. Breadth-First Search (BFS): This algorithm explores all the neighbor nodes at the present depth before moving on to nodes at the next depth level. It ensures the shortest path in an unweighted graph but does not optimize for cost.

2. Best-First Search: This algorithm selects paths that seem to be leading most quickly to the goal. It uses a heuristic to prioritize nodes. A* is often categorized under this, with a specific heuristic function to estimate cost.

3. Depth-First Search (DFS): This algorithm explores as far down a branch as possible before backtracking. It does not guarantee the shortest path in weighted graphs and utilizes less memory compared to BFS.

4. Bulkworld Problem: This is related to planning and not inherently related to pathfinding algorithms like A*.

Verify and Summarize

Given the definitions above, the A* algorithm fundamentally combines the "Best-First Search" strategy with a cost function. Therefore, it is most closely associated with:

Final Answer

b. Best-First-Search