单项选择题
A. When he saw Hollopeter fall, Wesley Autrey was waiting for someone alone.
B. When he saw Hollopeter fall, he thought over a long period of time before he jumped onto the tracks.
C. After he saw Hollopeter fall, he made a quick decision and pulled the young man out of the track as soon as possible.
D. After he saw Hollopeter fall, he quickly made a decision to protect Hollopeter from harm.