Q1. In the context of satellite remote sensing, the term 'spectral signature' of a surface material refers to which one of the following?
- A. The characteristic pattern of reflectance and absorption exhibited by the material across different wavelengths of the electromagnetic spectrum
- B. The smallest ground area, in metres, that a sensor can resolve as a single pixel
- C. The repeat-cycle period after which a sun-synchronous satellite revisits the same point on Earth
- D. The radiometric calibration coefficient applied to raw digital numbers from a sensor