Which of the following activities involves using electromagnetic energy to control the electromagnetic spectrum?

The activity that involves using electromagnetic energy to control the electromagnetic spectrum is Electronic Warfare. This field focuses on the use of directed energy or electromagnetic signals to disrupt or manipulate enemy communications and radar systems while protecting friendly assets. It includes actions such as jamming enemy radar and communications, conducting electronic surveillance, and using deceptive tactics to confuse adversary systems.

In contrast, Information Operations primarily deal with the dissemination and control of information to influence an audience and achieve strategic objectives. Network Defense concentrates on protecting computer networks from intrusion or attack, while Standard Military Operations refer to the overall conduct of military actions rather than a specific focus on electromagnetic energy. Thus, Electronic Warfare uniquely encompasses the manipulation of the electromagnetic spectrum for combat operations.