—May I come in？ I’m sorry I am late.

—Come in, please tell me       .

A、why you are late again       B、what were you doing

C、who did you talk with

点位的多少，布局是否合理，应以满足使用需要为准则，其精度应高于建筑物所需的定位精度，对测区起到控制作用。（）