Which fire control measure involves changing the rate of fire during offensive operations?

The choice of shifting fire is related to adjusting the rate or focus of fire during offensive operations. This tactic allows a unit to respond dynamically to the evolving battlefield conditions. By shifting fire, a crew can increase or decrease their rate of fire based on the immediate tactical situation, such as when engaging targets that appear or when supporting advancing infantry.

This flexibility is essential in maintaining effective suppressive fire or maximizing firepower at critical moments. For instance, if a squad is advancing and encounters enemy resistance, the machine gun team may shift their fire to suppress that resistance intensively, providing the necessary support for the infantry to maneuver effectively.

The other options represent different concepts; cease fire involves stopping all firing, commence fire signifies the beginning of fire, and displacement refers to moving the machine gun to a different location while maintaining the ability to engage targets. None of these directly involve the active adjustment of the rate of fire during the course of an offensive operation in the same manner as shifting fire does.