Four accounts of 'disappearance' of dinosaurs

According to one synopsis, there are so far four "theories" which tries to explain 'or account for the 'extinction of dinosaurs. 'It appears that the disappearance of the prehistoric creatures was not a single event but a process which occurred over a period of time. 'If it is a process, then could it be that 'more than one single factors were responsible '? In other words, 'the extinction of dinosaurs may not be a monocausal event but a multifactorial process. 'Meanwhile, it cannot be ruled out that 'even more 'theories' could be advanced by researchers in future.