单项选择题
A.0.16mm B.0.12mm C.0.17mm D.0.18mm
A.0.5~2mm B.0.2~2mm C.2~5mm D.20~50mm
A.GB/T17450-1998 B.GB/T17450-1996 C.GB/T17454-1998 D.GB/T17456-1998