How much on-disk space will be consumed for the data and protection overhead, excluding metadata?

A customer has 1,000 at 2 KB files, 5,000 at 4 KB files, and 4,000 at 7 KB files. They want to know the total amount of space on disk with a requested protection level of N+2d:1n.

How much on-disk space will be consumed for the data and protection overhead, excluding metadata?
A . ~146 MB
B . ~156 MB
C . ~164 MB
D . ~234 MB

Answer: D