Correct option is C
The primary purpose of the modulation feature in a function generator (or signal generator) is to simulate complex, real-world signals by modifying one signal (the carrier wave) with information from a second signal (the modulating wave). This allows the function generator to produce a variety of modulated signals (AM, FM, PM, etc.) that are used to test electronic equipment and communication systems. By applying modulation, the generated signal can cover a wider spectrum and mimic the characteristics of signals found in practical applications like radio broadcasting and wireless communication, making the generator more versatile.
