What storage capacity should be specified to scope the system with Tier 1 RAID 10 protection?

A customer requests a proposal for a new Dell EMC SC Series storage system with the following specifications:

– IO type: Random

– Existing data: 100 TB

– Rate of change: 2 TB per day

– Growth rate: 100 GB per day

– Snapshot retention: 1 week

What storage capacity should be specified to scope the system with Tier 1 RAID 10 protection?
A . 2.5 TB
B . 4.5 TB
C . 6.5 TB
D . 8.5 TB