Triple

Target class: frontier defense system
Context triple: [Ottoman defensive system on the Dniester, instanceOf, frontier defense system]

• A. border defense system
  A border defense system is an integrated network of physical barriers, surveillance technologies, personnel, and response protocols designed to monitor, control, and protect a nation's boundaries from unauthorized crossings and external threats.
• B. military fortification system chosen
  A military fortification system is an integrated network of defensive structures, obstacles, and support facilities designed to protect territory, forces, and strategic assets from enemy attack.
• C. naval defense system
  A naval defense system is an integrated network of sensors, weapons, platforms, and command-and-control components designed to detect, deter, and neutralize maritime threats to ships, fleets, and coastal assets.
• D. defense concept
  A defense concept is a high-level strategic framework that outlines how a state or organization plans to protect its interests, territory, and assets against potential threats through the coordinated use of military, political, economic, and technological means.
• E. ground-based air defense system
  A ground-based air defense system is a coordinated set of land-deployed sensors, command-and-control elements, and weapon platforms designed to detect, track, and engage airborne threats such as aircraft, missiles, and drones.
• F. None of above.