As I see it, I think people are being late because of different reasons. I used to come late, but when I realized it annoys other people, I tried to change this bad habit and it required a lot of work (but I managed to to that). It is not easy to change bad habits with a little work.
Some people are late because they do not realize it really annoys people and I think problem is related to the type of personality. Some people are late, because they have a lot to do, some are late because they are lazy. I would choose answer B.
