What was established by the Marine Corps in July 1798, the first of any of the services?

The Marine Corps Band, established in July 1798, holds the distinction of being the first of its kind among the United States military services. Often referred to as "The President's Own," this band is closely associated with the Marine Corps and the White House, performing at official functions and ceremonies. The founding of the Marine Corps Band was significant not only for military morale but also for the cultural heritage of the Marine Corps.

The other options, while important in their own right, were not the first to be established by the Marine Corps. The Marine Corps School and the Marine Corps Academy were developed later for training and education purposes, and the Marine Corps Museum is a modern establishment dedicated to preserving the history and traditions of the Corps. Thus, the establishment of the Marine Corps Band is a notable event that highlights the organizational commitment to music and ceremonial duties from the very early days of the Marine Corps.