Answer: D.adding more shelter for frogs
Food chain can be defined as the linear series of food and energy distribution, in which one organism is consumed by the other in order to obtain nutrient and energy.
In the given situation a person wants to reduce the mosquito population, which is present as a primary and secondary consume in the pond food chain. By adding more shelters for frogs can reduce the population of frogs as the frogs are present as tertiary consumers in the pond food chain. These frogs will feed upon mosquitoes, and limit their population.
