The correct option is B Different
Quality or Timbre of a sound is that characteristic which distinguishes the two sounds of the same pitch and loudness but emitted by two different instruments. It depends on the waveform. The waveform of a sound from an instrument depends on the presence of subsidiary vibrations along with the principal vibration and the relative amplitudes of various subsidiary vibrations in relation to principal vibration. Different instruments emit different subsidiary notes, e.g., a note played on a piano has a large number of subsidiary notes while a flute contains only a few subsidiary notes.