E8B08:What describes orthogonal frequency-division multiplexing (OFDM)?

Direct answer summary (2024-2028 NCVEC pool)

The official correct answer for E8B08 is A digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference.

The key fact is A digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.