Question 47

The Correct Answer is D **Explanation for Correct Answer (D):** Rule 35(e) of the International Regulations for Preventing Collisions at Sea (COLREGs), which applies to both International and Inland waters (as US Inland Rules generally parallel COLREGs for towing signals), specifies the fog signal for a vessel being towed or for the last vessel in a tow if manned. The required signal is **one prolonged blast followed by three short blasts** ($- \dots$). This signal is used at intervals of not more than 2 minutes. **Explanation for Incorrect Options:** * **A) One prolonged followed by two short blasts ($- \cdot \cdot$):** This is the required fog signal for a vessel restricted in its ability to maneuver (including dredging, underwater operations, etc.) and a vessel constrained by its draft. * **B) Two prolonged blasts ($\mathbf{- -}$):** This signal is used by a sailing vessel (Rule 35(c)) or a fishing vessel, or a vessel engaged in pushing or towing but not severely restricted in its ability to maneuver (Rule 35(c)), or a non-manned vessel being towed (Rule 35(f)). While a vessel being towed often uses a signal, two prolonged blasts are not the specific requirement for a *manned* vessel being towed. * **C) One prolonged followed by one short blast ($- \cdot$):** This is the required fog signal for a vessel at anchor (Rule 35(g)).