单选题 Male and female loons tend to act ______, actively helping each other forage for food to feed their young.
A. aggressively B. surreptitiously C. cooperatively D. defensively

【正确答案】 C
【答案解析】[考点] 副词辨析
[解析] 雄潜鸟和雌潜鸟常常相互配合地行动，积极帮助对方寻找食物来喂它们的幼鸟。C项“合作地”符合题意。