A yellow signal floating in the air from a small parachute, about 300 feet above the water, would indicate that a submarine __________.

Correct Answer: Option A — is about to rise to periscope depth

Under USCG Deck Safety, SOLAS Chapter III, and 46 CFR regulations, when addressing 'A yellow signal floating in the air from a small parachute, about 300 feet above the water, would indicate that a submarine', the mandated standard is: 'is about to rise to periscope depth'.