Which of the listed battery charging circuits is used to maintain a wet-cell, lead-acid, storage battery in a fully charged state during long periods of disuse?

Correct Answer: Option D — Trickle charging circuit

In USCG Marine Electrical Systems (IEEE 45 and 46 CFR), regarding 'Which of the listed battery charging circuits is used to maintain a wet-cell, lead-acid, storage battery in a fully charged state during long periods of disuse', the compliant technical standard is: 'Trickle charging circuit'.