A pushing vessel and a vessel being pushed ahead are rigidly connected in a composite unit. What fog signal shall this composite unit sound in restricted visibility?

1. A. One prolonged followed by two short blasts, because a pushing vessel is engaged in towing
2. B. One prolonged followed by three short blasts, as the last vessel of a tow
3. ✓ The signal prescribed for a power-driven vessel — one prolonged blast if making way, or two prolonged blasts if stopped and making no wayCorrect
4. D. No fog signal is required because the composite unit is neither a towing vessel nor a vessel being towed