What is the recommended reserve LUN size?

A colleague plans to use VNX Snapview Snapshots to make local copies of four data warehouse
LUNs. The LUNs to be snapped arE.
10 GB
20 GB
30 GB
100 GB
What is the recommended reserve LUN size?

A.
4 GB

B.
8 GB

C.
2 GB

D.
16 GB