What are the necessary steps to enable parallel content migration?

A.
Configure the maximum number of threads to use on the dm_docbase_config object instance

B.
Activate the Content Storage Services license only

C.
Activate the Content Storage Services license and then configure the number of threads to use
on the server config object

D.
Activate the Retention Policy Services license and then configure the maximum number of
threads to use on the server config object