A _____ consists of two or more targets on which fire is desired simultaneously.

The term that refers to two or more targets on which fire is desired simultaneously is known as a "Group of Targets." This terminology is commonly used in military operations, particularly in the context of artillery and field operations, to indicate a coordinated effort to engage multiple targets at once. The concept emphasizes the importance of synchronizing fire to maximize effectiveness and create a desired tactical effect on the battlefield.

When engaging multiple targets, artillery units need clear communication and coordination to ensure all elements are effectively targeting the designated locations at the same time. This ensures that the firepower is applied efficiently and that the targets are neutralized or destroyed as intended.

Other choices may suggest similar meanings but typically do not convey the specific military context or definitions used in operations. For instance, a "Collective Target Set" might imply a broader grouping of targets but does not specifically emphasize simultaneous engagement. "Series of Targets" and "Multiple Targets" also describe more generalized groupings without the specific connotation of coordinated, simultaneous fire. Thus, "Group of Targets" is the most accurate term to convey the intent of the question.