In this task, you will be given two sentences separated by ", so". You should decide whether the first sentence can be the cause of the second sentence. If you can see a possible causation, answer with "plausible", otherwise answer with "not plausible".

I was confused by the professor's lecture, so I looked it up on the internet
plausible

The papers were disorganized, so we had to start all over again
plausible

The boy murmured his reply to his mother, so it was good to see him again

not plausible