Final answer:
The Secretary of Defense conducts a comprehensive examination of the national defense strategy and other defense elements every 2 years.
Step-by-step explanation:
The Secretary of Defense (SECDEF) is required to conduct a comprehensive examination of the national defense strategy, force structure, force modernization plans, infrastructure, budget plan, and other elements of the defense program and policies of the United States on a specific schedule. This review process is critical for ensuring that the U.S. military remains well-equipped and prepared to face current and future challenges. the Secretary of Defense (SECDEF) in the United States is required to conduct a comprehensive examination of the national defense strategy, force structure, force modernization plans, infrastructure, budget plan, and other elements of the defense program and policies every two years. Therefore, the correct answer is: A) Every 2 years