Which equation represents a spherical wave?

Options

• Option A

  S = S₀ sin (Kx - ωt)

• Option B

  S = S₀ cos (Kx - ωt)

• Option C

  S = (S₀/x) sin (ωt - Kx)

• Option D

  S = (S₀/x²) sin(ωt - Kx)