question: What is one key advantage of OFDM (Orthogonal Frequency Division Multiplex) over DS (Direct sequence) spread-spectrum in a multiple access scenario? option 1: OFDM allows for higher channel capacity. option 2: OFDM has lower power consumption. option 3: OFDM maintains orthogonality across multiple users. option 4: OFDM is less susceptible to interference. option 5: All of the above 