2. 依據Rule 8 (c) If there is sufficient sea-room, alteration of course alone may be the mosteffective action to avoid a close-quarters situation provided that it is made in good time, issubstantial and does not result in another close-quarters situation.，以下何者符合close-quarterssituation的定義？
(A) CPA接近於0就算
(B) 相對方位沒有明顯變化就算
(C) 雙方有碰撞危機存在就算
(D) 靠單方採取避讓行動，已無法解除碰撞危機就算