Last night was the worst night of the trip as far as the rolling of the ship . When it gets like this , things really move around -- cabinet doors that are not tightly secured fly open and the contents spill out on the floor . When we woke up there were papers on the floor that had vibrated off the desk and one of the cabinets had spilled out . The library in the lounge had disgorged all of its books which were spread from one end of the room to the other , plus the scrabble pieces were also dumped out .

Based on the preceding passage, choose your answer for question Why did the the books end up on the floor ?

a). Because the bookshelf had collapsed ..
b). Because the toddler threw them ..
c). Because they were in the process of moving ..
d). Because the ship hit rough water ..
The answer is:
d).