【单选题】听力原文:M: Look, the lights in the lab are still on. It must be Professor Zhang who is still in it. W: How could it be? I saw her go home just a moment ago. What does the woman mean?
A.
Professor Zhang couldn't be in the lab.
B.
Professor Zhang forgot to turn off the lights in the lab.
C.
Professor Zhang went home a long time ago.
D.
Professor Zhang was the last one to leave the lab.