在Kubernetes集群中通过标签可以将应用Pod进行灵活调度，下面哪个是正确删除节点标签的操作（）。
Akubectl lables node-1 key=value
Bkubectl lables node-1 key-
Ckubectl lables delete node-1 key=value
Dkubectl lables delete node-1 key-
Akubectl lables node-1 key=value
Bkubectl lables node-1 key-
Ckubectl lables delete node-1 key=value
Dkubectl lables delete node-1 key-