Answer:
D). A backup energy source is required to make up all short falls.
Step-by-step explanation:
Wind is a renewable source of energy as wind can be replenished in nature. It is an alterntive source of energy which reduces some dependency over the use of conventional sources of energy like fossil fuels.
As the weather condition can influence the direction as well as speed of the wind currents . Therefore, it cannot be consider as a reliable source for availing the daily energy needs. Hence, a backup is required to meet the energy needs when no or very few amount of energy could be harnessed by wind power plant.