Quiz: Multi-Source BFS

In the Rotting Oranges problem, you push all rotten oranges into the queue before starting BFS. What would go wrong if you ran a separate BFS from each rotten orange instead?

1. A.The answer would be wrong because BFS cannot run multiple times
2. B.Nothing. Both approaches give the same result with the same speed
3. C.Separate BFS runs would miss some fresh oranges
4. D.Separate BFS runs give the correct answer but take $O(k \cdot V)$ time instead of $O(V)$, where $k$ is the number of sources