Which of the following is an example of a physical distraction to listening?

A. "Are you kidding? All I could think about was my vacation that starts tomorrow."
B. "I could not pay attention to anything she said after she mentioned feminist theory."
C. "The two people talking in the row ahead of me kept me from catching very much of his lecture."
D. "I didn't know what he said because I was so worried about what the kids were doing in my absence."

Answer: C