Which of the following statements about the optical-layer interfaces OTM-n.m and OTM-nr.m of OTN is incorrect?

Which of the following statements about the optical-layer interfaces OTM-n.m and OTM-nr.m of OTN is incorrect?
A . n indicates the number of wavelengths carried by the maximum capacity,
B . m indicates the rate. The value can be 1, 2, or 3.
C . r indicates OTM without the OSC function..
D . OTM-nr.m with OSC signals is OTM-n.m.

Answer: B