Which operations focus primarily on defeating enemy attacks before they can affect friendly forces?

The correct answer is OCA, which stands for Offensive Counter Air operations. These operations are specifically designed to seek out and eliminate enemy aerial threats before they can reach or impact friendly forces. The primary objective of OCA operations is to maintain air superiority and protect friendly assets from enemy air attacks. This involves engaging enemy aircraft, targeting their air bases, and disrupting their capabilities to launch further attacks.

In contrast, DCA, or Defensive Counter Air operations, focus on defending against incoming attacks rather than preemptively striking at enemy targets. Support Operations and Relief Operations, while important for comprehensive military strategy, do not directly address the immediate concern of countering enemy aerial threats proactively. Thus, OCA is the clear choice when the goal is to prevent enemy attacks from interfering with friendly forces.