People often like collecting things. Collecting stamps, books, pictures and pens are some common hobbies. I know many kinds of collections. but do you know the collection of clocks? My friend Mr. Clock, a short man, has the hobby. He has one thousand five hundred clocks. There are clocks here and there in his house. You can see lots of clocks on shelves. As there is not enough room for so many clocks, the man has to put clocks into some boxes under the beds in his house. Mr. Clock likes his large collection of clocks, but his wife,Mrs. Clock does not enjoy them at all. She complains every day because she has to do much work,for it is not easy to clean hundreds of clocks. She also complains about the noise. Each clock keeps a different time. So she can hear the chimes almost any time day and night. There is something even worse. With so many clocks around, she is never able to know the correct time! Mrs. Clock complains every day because   _  .
she has to clean many clocks she can hear the chimes any time at home she can't know the correct time A, B and C