Due to a local party in my neighbourhood I was only able to sleep 4hrs . So the early get up at 4 hitted quiet hard . Leaving a bit later than scheduled and a miscalculated train departure time at my city made me just miss my train . But I still got to the Airport around 8AM .

Question: What may be the reason for their lack of sleep ?
Answer: They had stayed a party for too long .The party near them was too loud .None of the above choices .They had drank too much at the nearby party .