When multiple admissible heuristics are available for a problem, and none of them dominates any of the others, a common approach is to combine them. The idea is to create a new heuristic that benefits from the strengths of each individual heuristic. One such approach is to take the maximum (max) value of the individual heuristic
Therefore, the correct choice would be:
A. $h(n)=max((h_i(n),…,h_m(n))$