The key idea is that this WW2 hand-to-hand system was shaped by a mentor-student line where practical battlefield experience was fed back into training. Col. Rx Applegate is identified as the protégé who worked directly with William E. Fairbairn and Eric A. Sykes, taking their techniques and refining them based on actual combat feedback. That real-world input was crucial for turning combat principles into usable, battlefield-tested methods, which is why this person is highlighted in relation to developing the system. In contrast, while the other individuals may have their own roles in military or martial contexts, they aren’t the ones historically linked as the direct student who carried Fairbairn and Sykes’s methods forward through battlefield feedback.

Jitsu refers to technique or the practiced method of applying skills in combat. It captures the practical, systematic ways to execute moves and counters, often rooted in battlefield use. That focus on technique and how to apply it in real scenarios makes the description about science-like study of techniques and battlefield methods the best fit. The other ideas describe a philosophical path (do), sport-oriented competition, or etiquette and self-control, which aren’t what jitsu specifically denotes.

When you don’t know what you’re walking into, your first priority is to create space and assess the situation. Giving yourself distance buys you time to observe body language, look for potential threats, and identify possible exits or help. This pause helps you decide the safest course of action rather than rushing in or escalating the encounter. Creating space reduces the chance of a rapid, uncontrollable attack and keeps you in a position where you can retreat or seek assistance if needed. It also lowers your own adrenaline-driven reaction, making it easier to think clearly and act deliberately. Engaging immediately can escalate the situation and leave you more exposed. Running away without assessing might lead you toward danger or into a spot where exit options vanish. Confronting and shouting commands often provokes a hostile response and can put you at risk if you’re not in a position of control. So, prioritizing space and assessment sets you up with safer options and helps you respond more effectively if the situation escalates.

When someone grabs you from behind, your first goal is to create space and reorient to face the threat. Step away to break the grip and lower your center of gravity so you don’t get pulled off balance. Turn toward the attacker so you can see their hands and begin your escape, while keeping your hands up to guard your head and torso. This position lets you disengage safely and regain distance to move to a safer spot. Other options tend to keep you attached to the grip, throw you off balance, or leave you exposed to follow-up actions, so this approach offers the quickest, clearer path to freedom.

Mount control means you are on top of your opponent with your hips centered over theirs, keeping your weight over their torso to pin and control them. This position uses gravity and a solid base to limit their movement, making it hard for them to bridge or escape. From here you can control their upper body with your hands and frames while staying balanced and ready to attack or transition, which is why being on top with the hips over the opponent is the defining feature of mount control. Being on the bottom or standing aren’t descriptions of mount control, so those options don’t fit as well.