3. 下圖所示之國際信號旗為何？ (A) V (B) X (C) M (D) S

12. A vessel is seen showing three shapes in a vertical line; the top and bottom ones are black balls and the middle one is a black diamond. What does this daytime signal indicate? (A) It is a vessel engaged in dredging. (B) It is a vessel restricted in her ability to manoeuvre. (C) It is a vessel at anchor. (D) It is a vessel engaged in a mine clearance operation.