A) 3 kHz
Single Sideband is also referred to as SSB. The transmitted bandwidth of an SSB signal is dependent on the particular rig being used. A common transmitted bandwidth is 3 kHz. SSB receivers often include one or more filters which can further reduce received bandwidth (e.g. 2.8 kHz, 2.4 kHz, 1.9 kHz). Filtering can improve intelligibility of weak signals received in crowded conditions.