Which type of gun salute is NOT authorized?

The 10-gun salute is not an authorized military salute. Military honors are typically conveyed through prescribed numbers of cannon salutes that have historical significance and specific usage. A 21-gun salute is a traditional highest honor given for notable occasions, including the arrival of foreign dignitaries and other state events. The 13-gun salute is often reserved for specific individuals, such as certain ranks or positions, and is used in ceremonies to reflect respect.

In contrast, the 17-gun salute does exist and is designated for particular honoring situations within certain contexts, though it's less common than the 21-gun and 13-gun salutes. Ultimately, the key takeaway is that the number of guns fired in these salutes follows established traditions, and since the 10-gun salute does not align with any of these ceremonial standards, it is not authorized.