A minimum instrument altitude for enroute operations off of published airways which provides obstruction clearance of 1,000 feet in nonmountainous terrain areas and 2,000 feet in designated mountainous areas within the United States is called
A.Minimum Obstruction Clearance Altitude (MOCA).
B.Off-Route Obstruction Clearance Altitude (OROCA).
C.Minimum Safe|Sector Altitude (MSA).
正确答案是B