Which command creates a new SyncMirror aggregate, letting Data ONTAP select the disk drives?

A.
aggr create aggrX -d 12

B.
aggr create aggrX -m 12

C.
aggr mirror aggrX -m 12

D.
aggr mirror aggrX -n 12

Explanation:
https://library.netapp.com/ecmdocs/ECMP1196890/html/man1/na_aggr.1.html
The following commands are available in the aggr suite:
add mirror restrict undestroy
copy offline scrub verify
create online show_space
destroy options split
media_scrub rename status
aggr create aggrname
If you use the -d disk1 [ disk2 … ] argument, the node creates the aggregate with the specified spare disks
disk1, disk2, and so on. You can specify a space-separated list of disk names. Two separate lists must be
specified if the new aggregate is mirrored. In the case that the new aggregate is mirrored, the indicated disks
must result in an equal number of disks on each new plex.
The disks in a plex are not permitted to span spare pools. This behavior can be overridden with the -f option.
The same option can also be used to force using disks that do not have matching rotational speed. The -f
option has effect only when used with the -d option specifying disks to use.
The -m option can be used to specify that the new aggregate be mirrored (have two plexes) upon creation. If
this option is given, then the indicated disks will be split across the two plexes. By default, the new aggregate
will not be mirrored.
aggr mirror aggrname
The -n option can be used to display the command that the system will execute without actually making any
changes. This is useful for displaying the automatically selected disks, for example.