What type of command consists of forces from more than one allied nation?

The correct answer is combined command, which refers to forces that are composed of military units from multiple allied nations working together towards a common goal. This type of command is essential in joint operations, where interoperability between different armed forces is crucial for mission success. Combined commands allow for the pooling of resources, sharing of intelligence, and coordinated efforts in strategy and tactics, which enhances operational effectiveness on a multinational scale.

Unified command, while also involving multiple forces, specifically pertains to a joint command structure imposed under a single commander for a particular operation or campaign that may include forces from the same nation or allied nations. Major commands and direct reporting units are organizational structures within a single military service and do not typically involve multinational forces. Thus, combined command is the most appropriate designation for forces drawn from various allied nations.