Context: I get to the merge point , and he goes flying right through his stop sign . I have to slam on my brakes , I lay on the horn ... at least he bothered to realize " Oh , shit , I just fucked up , did n't I ? " And pulled over for a second to make sure he did n't make me go flying off the road or anything . But only for a second , then he starts up again , waves his hand out the window in an attempt to say ' sorry , ' and turns up into the development .

Question: What may be the reason for laying on the horn ?
Options:
0. For the person to apologize .
1. For the person to revoke their license .
2. For the person to pull over and explain why they did that .
3. For the person to realize they messed up .
Answer: 3