MARSEC Level 3 is defined as which of the following?

• A. Baseline
• B. Increased security posture
• C. No change in security posture
• D. CG's most focused security posture, attack is deemed imminent

Answer: (D)

MARSEC levels describe how maritime security measures are escalated in response to threats. At MARSEC Level 1 the posture is baseline, with normal security procedures. MARSEC Level 2 raises security measures in response to elevated risk. MARSEC Level 3 is the highest level, used when an attack is deemed imminent or a security incident is likely, prompting the most stringent security actions across operations. Therefore, the statement describing CG's most focused security posture because an attack is deemed imminent matches Level 3. The other options correspond to lower levels or no change in security posture.