Explanation/Reference:
* DPM protection supports the following scenarios:
/(this scenario) Protects virtual machines that are hosted on stand-alone servers that run Hyper-V and that use local or directly attached storage.
/Protects virtual machines that run on a cluster. The cluster uses Cluster Shared Volumes (CSV) storage.
/Protects virtual machines that run on a stand-alone server or cluster and that use SMB 3.0 file server storage.
/Protects virtual machines that are running during a live migration.
* Example: Protection for virtual machines on a stand-alone server that is running Hyper-V

This configuration protects one or more virtual machines on a stand-alone host computer. Storage can be local on the host server, or directly attached to it, for example a hard drive, a storage area network (SAN) device, or a network attached storage (NAS) device. Alternatively, the host server might use SMB 3.0 storage on an alternate file server. The DPM protection agent must be installed on all hosts and on the file server if storage is hosted by using SMB 3.0.
Incorrect:
Not B: Would not minimize the number of Protection Agents.
Ref: https://social.technet.microsoft.com/wiki/contents/articles/17493.protecting-hyper-v-virtual-machines- with-system-center-dpm-2012.aspx