Unseen operation in the same band as other types of wireless services, i.e. without interfering with those services, is a feature of what type of modulation technology?
A. QAM
B. FHSS
C. GFSK
D. 5G cellular
E. A & B
F. B & C
G. B & D
H. B & E
I. D & E
J. None of the above.