An algorithm A is admissible if ___________ A. It is not guaranteed to return an optimal solution when one exists B. It is guaranteed to return an optimal solution when one exists C. It returns more solutions, but not an optimal one D. It guarantees to return more optimal solutions

The correct answer is: B. It is guaranteed to return an optimal solution when one exists.

An admissible algorithm is one that always returns a solution that is no worse than the optimal solution. In other words, if an optimal solution exists, then an admissible algorithm will always find it.

Option A is incorrect because an admissible algorithm is guaranteed to return an optimal