Quiz: Labyrinth Pattern

Labyrinth: Find shortest path in a grid from 'A' to 'B', avoiding walls. How do you model this as a graph problem?

1. A.Only 'A' and 'B' are nodes, find direct path
2. B.Walls are nodes, empty cells are edges
3. C.Each row is a node
4. D.Each cell is a node, edges connect adjacent non-wall cells