Final answer:
The answer is True. The Base Support Plan is essential for preparing military installations for contingency operations by detailing resources and support capabilities.
Step-by-step explanation:
True, the Base Support Plan does determine an installation's capabilities and outlines how those capabilities will be applied during contingency operations. This planning is vital for military installations to be prepared for various situations that may arise, requiring quick adaptation and efficient use of resources and personnel. The Base Support Plan is a comprehensive document that ensures readiness by detailing the available support and resources, including communication, security, logistics, medical services, and civil engineering, among others, and how they will be coordinated and employed.