Answer:
Option (3)
Explanation:
In astronomy, the redshift refers to the shifting of the beam (spectrum) of light towards the light of higher wavelength. The red coloured light has the highest wavelength. This shifting of light is due to the doppler effect, which states that the wavelength of light changes when the light source and the observer are constantly in motion with respect to each other.
Based on this observation and many other scientific investigations, the scientists have concluded that the redshift data indicates the expansion of the universe, where the distant galaxies are moving constantly and rapidly away from us.
Thus, the correct answer is option (3).
