Correct answer: A). The energy of the photon is directly proportional to frequency.
A photon is a quantum of electromagnetic radiation, and quantum is the smallest unit of quantity. Thus the photon is the smallest unit of light. The energy is directly proportional to the frequency of the photon and inversely proportional to wavelength.
It means higher the frequency of photon greater will be its energy and lesser will be its wavelength.
The population growth or population recovery will be an exponential growth curve. The linear fit on the given data will help model the recovery of the population in future time. The attached image shows the linear fit and its extrapolation till the year 3000. The linear fit gives a good underestimate of the population in the years after 2530. Hence the answer is D. a date in the distant future.