Answer:
Option D
Explanation:
In general a sample collected from a set of naturally distributed data set must also follow the bell curve or natural distribution
In other way round it can be said that sample set must have the same characteristics as that of the main set and hence a sample must be representative of the population.
Option D is correct
A reflected wavelength of light is detected by the detector and is decoded as a logic one; absorbed or transmitted wavelengths are not detected, there absence being decoded as a logic zero.