Which among the following statement(s) is(are) FALSE?

A. Greedy best‐first search is not optimal but is often efficient.

B. A* is complete and optimal provided h(n) is admissible or consistent.

C. Recursive best‐first search is efficient in terms of time complexity but poor in terms of space complexity.

D. h(n) = 0 is an admissible heuristic for the 8‐puzzle.