What is the minimum number of fabric modules that should be installed in the Cisco Ne*js 7000 chassis for N 1 redundancy using Ml-Series line card?

What is the minimum number of fabric modules that should be installed in the Cisco Ne*js 7000 chassis for N 1 redundancy using Ml-Series line card?
A. 3
B. 4
C. 5
D. 6