单选题 Professor Collins was ______ of the latest developments in physics because he had been in hospital for several months.
【正确答案】 D
【答案解析】[解析] 句意：科林斯教授对最新的物理学发展一无所知，因为他已经住院好几个月了。be ignorant of不知道，不了解。be unconscious of没有意识到。其它两项搭配错误。