F: We're going to listen to a lecture about environmental protection. ,M: Really? I thought we'd go to see an exhibition.
(A) F: It's a lecture about environmental protection. So let's go to see the exhibition. (B) F: It's a lecture about air pollution. So let's go to see the exhibition. (C) F: It's a lecture about exhibition. (D) F: I’m sorry, I don’t understand. Could you say it again?
A