A: Obviously the first person is writing something or studying. Probably in his own room. The reason I think so is because he has so many things on his table and next to him is a wall full of photos.
B: I'm not one hundred percent sure where that is taking place but it looks like they are in a Computer Lab or somewhere like a room with many computers. In the background there are some people who seem to work on PC's
C: In this image we can see a person who tries to make money possibly for charity actions. Or he may be just be selling advertisements.
D: The fourth image is very simple to explain. That guy is at work, writing something on his computer. As we can see he is a little stressed out or maybe he is just concentrating
