【题目】The explorer got a disease in blood for ________of fresh vegetables and fruit.
A.sake
B.lack
C.ignorance
D.knock

【答案】B
【解析】考查名词。for the sake of为了……的缘故；for lack of由于缺少；ignorance无知；knock敲打，敲击。句意：探险家因为缺少新鲜的蔬菜和水果，得了一种血液病。根据句意应选B。