1．They are just college graduates and don’t realize ________ to start and run a company.
A．what takes it B．what they take
C．what takes them D．what it takes
解析：选D。句意：他们是刚毕业的大学生，还没有认识到开办和经营一家公司需要什么。在realize的宾语从句中，用了固定句式：It takes(sb.)sth./some time to do sth.“花费(某人)……做某事”，what引导宾语从句，同时在从句中作take的宾语。
