Which of the following concepts emphasizes mutual respect and understanding between different Christian denominations?

The concept that emphasizes mutual respect and understanding between different Christian denominations is ecumenism. Ecumenism is focused on fostering unity among various branches of Christianity, promoting dialogue, cooperation, and reconciliation among these groups. It seeks to overcome historical divisions and encourage Christians to work together in areas of common concern, thereby enhancing mutual respect and understanding.

Pluralism, while it involves the coexistence of diverse religious beliefs and practices, does not specifically target Christian denominations or seek active dialogue among them. Secularity refers to the separation of religion from civic affairs and government, and it does not inherently promote mutual respect among religious groups. Fundamentalism denotes a strict adherence to specific theological doctrines, often leading to a rigid stance against differing beliefs, which goes against the spirit of mutual understanding sought in ecumenism.