单选题 The flies buzzing and whizzing around their ears kept them from finishing the experiment at the swamp.
【正确答案】 D
【答案解析】解析：句意：苍蝇在他们耳边不停嗡嗡嘤嘤的，吵得他们在沼泽地没法完成实验。句中“buzz”，“whiz”都是苍蝇的叫声，是拟声词，故答案为D。