单项选择题

Public and Private Schools in the Unite States
Religious and private schools receive little or no support from public taxes in the Unite States, and, as a result, are usually somewhat expensive to (51) . The largest group of religious schools in America (52) by the Roman Catholic Church. While religious schools tend to be (53) expensive than private schools, there are usually some fees.
When there is free education available to all children in the Unite States, why do people (54) money on private schools Americans offer (55) great variety of reasons for doing so, including the desire of some parents to (56) their children to schools (57) classes tend to be smaller, or where religious instruction is included as part of the educational program, or because, (58) their opinion, the public schools in their area are not (59) high enough quality to meet their needs. Private schools in the Unite States (60) widely in size, quality, and in the kind of program that are offered to meet (61) of certain students.
The degree (62) American parents are active in their children’s schools is often (63) to people of other countries. Most schools have organizations (64) of both parents and teachers, usually called P. T. A for Parent-Teacher-Association. They meet together to (65) various matters concerning the school. Parents often give their time to help with classroom or after school activities.

A.on which
B.to which
C.which
D.what