Final answer:
The correct answer is that the longer light has been traveling through expanding space, the more strongly redshifted it will be. This is due to the stretching of light waves as space itself expands, resulting in an increased wavelength, known as a redshift.
"the correct option is approximately option C"
Step-by-step explanation:
The effect of the expansion of space on light as it travels through the universe is a fundamental concept in cosmology. The correct answer to how this expansion affects light over time is: c. the longer the light has been traveling, the more strongly redshifted it will be. This phenomenon occurs because as the universe expands, the space through which light travels also stretches, thereby stretching the light waves. This stretching translates into an increase in the wavelength of the light, which we observe as a redshift. Hence, the farther away a galaxy is, the longer its light has traveled through expanding space, and the greater the redshift will be. It is important to note that this redshift does not imply a slowing of the light's velocity, but rather a change in the light's wavelength and frequency.
The concept of redshift is not only associated with the relative motion of celestial bodies, but it can also result from the expansion of the universe itself. Redshifts provide critical insights into the rate of expansion of the universe and hence, its age and the amount of matter and dark energy it contains. This stretching of light also gives rise to the concept of cosmological redshift, which is distinctly different from gravitational redshift — the latter being caused by the influence of gravity on light as it moves through space-time.
To maintain the constant speed of light, as postulated by Einstein's theories of relativity, the decreased frequency due to the redshift is compensated by a longer wavelength. In summary, the more the space has expanded since the light left its source, the greater the redshift observed.