Which of the following is a primary function of the J3 joint staff?

The primary function of the J3 joint staff is focused on operations and plans related to engagement. The J3 is responsible for the planning, coordination, and execution of military operations. This includes developing strategies for engagements and ensuring that operational plans align with the overall mission objectives of the joint force. The emphasis on operations reflects the J3's role in facilitating and overseeing activities that involve combat and engagement with adversaries, as well as ensuring readiness and effective response capabilities.

In contrast, resource management pertains more to logistical and financial aspects, which is typically under the purview of other staff sections. Personnel support, while crucial for maintaining operational effectiveness, is generally a function associated with the J1 staff. Intelligence gathering, which is essential for informed decision-making, falls within the responsibilities of the J2 staff. Thus, engaging in operational matters is the primary focus of the J3, distinguishing it from the other functional areas.