Final answer:
The simplest RAID storage design that writes data to two drives at the same time is known as mirroring (RAID 1), which provides high data redundancy and reliability.
Step-by-step explanation:
The simplest RAID storage design that writes data on two drives at the same time is called mirroring, which corresponds to RAID 1. With RAID 1, every piece of data is written identically to two separate drives, creating a mirror image, which ensures data is not lost if one drive fails. This method does not increase storage efficiency but provides a high level of data redundancy and reliability.
It's different from striping, which is RAID 0, where data is split across drives to improve speed and capacity but does not provide redundancy. Duplicating is not a RAID term, and divesting is unrelated to RAID configurations.