Under the regulations implementing MARPOL,
题型：单项选择题
问题：
Under the regulations implementing MARPOL, a mobile offshore drilling unit is required to have an International Oil Pollution Prevention (IOPP) certificate when the unit （）.
A.is drilling on the Outer Continental Shelf
B.moves to a new drilling location in U-Swaters
C.engages in a voyage to a port of another country which is a party of MARPOL
D.All of the above