Step 1: Understanding Fourier transform.
Fourier Transform (FT) converts a spatial domain signal into its frequency domain representation.
Step 2: Explanation of the given options.
- Chromacity Plot: Represents color distributions, not frequency analysis.
- Band Spectral Scatter Plot: Used in hyperspectral analysis but does not involve Fourier transformation.
- Frequency Spectrum: Fourier Transform converts signals from the spatial domain into the frequency domain for analysis.
Step 3: Selecting the correct option.
Since Fourier Transform operates in the frequency spectrum, the correct answer is c. Frequency spectrum.