Daily Chinese Test: What does the boss mean?

Intermediate Level 中级 (zhōngjí)
Conversation:
Mike is at his boss’s door; he knocks to enter.
Mén kāi zhe, jìnlai ba.
Boss: 门 开 着，进来 吧。
Lǎobǎn, zhè shì nín yào de wénjiàn.
Mike: 老板， 这 是 您 要 的 文件。
What does the boss mean?
A. The door is open.
B. The door is closed.
C. Wait a moment.

See answer and analysis at http://resources.echineselearning.com/minitestanswers/minitestanswers-chinese-746.html?ecl=ptEEEEEEpg080704