Explanation: Generating a single-sideband (SSB) phone signal typically involves a two-step process to remove the carrier and one of the sidebands from a standard Amplitude Modulated (AM) signal. The correct method, D) **By using a balanced modulator followed by a filter**, works as follows: First, an audio signal and a radio frequency (RF) carrier are fed into a **balanced modulator**. This circuit's function is to suppress the carrier frequency while producing the upper and lower sidebands, resulting in a Double Sideband Suppressed Carrier (DSB-SC) signal. Second, this DSB-SC signal is passed through a highly selective **filter** (such as a crystal, mechanical, or DSP filter). This filter removes one of the sidebands, leaving only the desired single sideband, which is then amplified and transmitted. Let's look at why the other options are incorrect: A) **By driving a product detector with a DSB signal:** A product detector is used for *demodulating* (receiving) SSB, CW, or DSB signals, not generating them. B) **By using a reactance modulator followed by a mixer:** A reactance modulator is primarily used to generate *Frequency Modulation (FM)*, not SSB. C) **By using a loop modulator followed by a mixer:** "Loop modulator" is not a standard or common term for SSB generation in amateur radio theory.