Which file system is both new and now installed by default in Oracle Linux 6 with Unbreakable Enterprise Kernel (UEK)?

Which file system is both new and now installed by default in Oracle Linux 6 with Unbreakable
Enterprise Kernel (UEK)?

A.
ext4

B.
ext3

C.
zfs

D.
ext2

E.
fat64

Explanation:
Oracle Linux 6 includes many new features, including:
ext4 filesystem
The ext4 filesystem is installed by default.