决断速度V1、发动机失效速度Vef、飞机地面最小操作速度Vmcg三者之间的关系是:
A.Vmcg<=Vef<=V1
B.Vef<=Vmcg<=V1
C.V1<=Vmcg<=Vef
D.Vmcg<=V1<=Vef
正确答案是A