【正确答案】 A

【答案解析】[听力原文]
W: Did you hear the thunder last night?
M: Did I? It was really loud.
W: I didn"t see any lightning, though. I thought that thunder and lightning always occur at the same time.
M: They do. It"s no possible to have one without the other since thunder is a direct result of lightning.
W: Really?
M: Yes. Thunder is caused by the rapid expansion and contraction of highly heated air along the path of an electrical discharge.
W: In other words, lightning quickly heats the air and causes thunder. But if the lightning is there, why can"t we see it?
M: Because it sometimes occurs very high in the clouds.
W: I wonder if it"s possible to see the lightning and not to hear the thunder.
M: Yes. It"s possible if the lightning flashes far enough away. Sound doesn"t travel as far as light.