单选题 Very few people understood his lecture, the subject of which was very ______.
【正确答案】 B
【答案解析】obscure模糊不清的，晦涩的；intelligible可以理解的，能懂的；dim暗淡的；Conspicuous引人注目的，突出的。句意：没几个人能听懂他的讲座，因其主题十分晦涩。