Which of the following is a type of fuse used on mortar rounds?

The option that identifies a type of fuse used on mortar rounds is the Near Surface Burst (NSB). This fuse is designed to detonate the mortar round just above the ground, maximizing the area of effect for the explosion. The NSB is particularly useful for targeting dispersed enemy personnel or equipment, allowing the blast and shrapnel to be distributed over a wider area, which increases the effectiveness of the munitions in specific tactical situations.

In contrast to this, other types of fuses mentioned do not specifically refer to those commonly used in mortar rounds. An impact fuze typically activates upon contact with the target, which is common in artillery but not exclusive to mortar rounds alone. Delayed activation fuzes may be used in various munitions but are not specific to mortar applications. Ground contact fuses, while they can be used in some artillery shells, do not capture the particular mechanism and purpose that the NSB fuse provides in mortar technology. Understanding the nuances of each fuse type and their intended applications is crucial for proper usage and maximizing effectiveness in combat scenarios.