A high court in Ghana has dismissed the local MTN unit’s challenge to a move by the national telecommunications regulator aimed at exposing it to greater competition, the company said on Thursday. In June, MTN appealed a decision by the National Communications Authority (NCA) to designate it a significant market power, a move that requires the regulator to take corrective action. But in a Sept. 1 decision, the court “dismissed the company’s application,” MTN said in a statement. It said it maintained its position that the NCA’s decision was unfair from a procedural standpoint and would “explore all available options…