通读下面的矩文，掌握其大意。然后，从每小题的四个选择项中选出可填入相应空白处的最佳选项。

　　Sometimes I feel that being the mother of three small children is like operating a large circus（马戏团）. 　21　 afternoon last week, my three sons playing peacefully in the back yard （院子）, 　22　 the ball from one to another. I jumped at the chance to talk to one of my friends 　23　 the phone, but before I 　24　to the phone, l could tell the boys had begun to quarrel with each other about something. I rushed out to 　25　 peace, but before I got there Charles had 　26　 a rock at Mark, and hit him in the eye. By the time I got to the back yard, they had begun to _　27　 about this. Even David, the oldest boy , who won't usually fight with anybody about 　28　, was involved（卷入）. First, l _　29　 them stop fighting, and then I examined Mark's eye. I decided that it wasn't going to develop into a black eye, but I felt that they should 　30　 at least a little for 　31　 they had done. "I'm going to 　32　 to your father about this when he comes home tonight," I said. "He and I will think of how to punish you." Things were 　33　 quiet after that for about half an hour, and then Charles 　34　 a glass in the kitchen, and at almost the same 　35　, Mark fell out of the apple tree.

____.

• A.through
• B.in
• C.on
• D.by