The numbering of domestic regional air lines falls into two cate

The numbering of domestic regional air lines falls into two categories: _______ used between the flight control regions, and _______ used within the flight control regions.

A.J1-200、J201-900

B.JA-200、JB-900

C.JK-100、JN-18

D.J-100、J120

正确答案是A