Which three of the components would degrade performance if used in a ZFS storage pool, and are not recommended configurations?

Which three of the components would degrade performance if used in a ZFS storage pool, and are
not recommended configurations?

A.
a file on a UFS file system

B.
a Veritas Volume Manager (VxVM) volume

C.
a LUN in a hardware RAID array

D.
a disk slice from an SMI labeled disk

E.
a Solaris Volume Manager (SVM) volume

F.
an EDI disk

Explanation:
A: ZFS also allows you to use UFS files as virtual devices in your storage pool. This
feature is aimed primarily at testing and enabling simple experimentation, not for production use.
The reason is that any use of files relies on the underlying file system for consistency. If you create
a ZFS pool backed by files on a UFS file system, then you are implicitly relying on UFS to
guarantee correctness and synchronous semantics.
However, files can be quite useful when you are first trying out ZFS or experimenting with more
complicated layouts when not enough physical devices are present. All files must be specified as
complete paths and must be at least 64 Mbytes in size.
B, E: You can construct logical devices for ZFS using volumes presented by software-based
volume managers, such as Solaris Volume Manager (SVM) or Veritas Volume Manager (VxVM).
However, these configurations are not recommended. While ZFS functions properly on such
devices, less-than-optimal performance might be the result.
Reference: Solaris ZFS Administration Guide, Managing ZFS Storage Pools