What is the defensive mission of the Marine rifle squad?

The defensive mission of the Marine rifle squad is fundamentally about protecting a designated area or position from enemy forces. The primary objective is to repel enemy assaults using a combination of firepower and close combat tactics. This involves effectively engaging the enemy to disrupt their advances and preserve the integrity of the defensive position.

In a defensive scenario, the squad utilizes its weapons and tactical formations to maximize their fire effect, aiming to create a formidable barrier against enemy incursions. Close combat is also critical, as it allows the squad to engage the enemy directly if they breach the initial layers of defense or approach within effective range. The emphasis is on maintaining defensive posture, ensuring that the squad can withstand and counterattack when necessary.

The other choices pertain to different tactical missions. While advancing into enemy territory, gathering intelligence, and establishing strongholds for attack each represent strategic operations, the defensive mission specifically focuses on the immediate need to protect and defend against enemy actions. Therefore, the characteristic that defines the correct answer is aligning with the primary purpose of defensive operations in a military context.