The correct answer is B.
OBJ-2.4: Modulation is the process of varying one or more properties of a periodic waveform, called the carrier signal, with a separate signal called the modulation signal that typically contains information to be transmitted. WiFi can use different digital modulation schemes for data transmission. Common types of modulation include Orthogonal frequency-division multiplexing (OFDM), Quadrature Amplitude Modulation (QAM), and Quadrature Phase-shift keying (PSK). Frequency is the number of occurrences of a repeating event per unit of time. Wireless networks utilize three different frequency bands: 2.4 GHz, 5 GHz, and 6 GHz. Interference occurs when two radios are transmitting or receiving on the same frequencies. Spectrum refers to the range of frequencies used by a radio transmitter or receiver, such as the 2.4 GHz spectrum which includes frequencies from 2.412 GHz to 2.472 GHz in the United States.