Which of the Following Is an Example of Density-Independent Population

Which of the following is an example of density-independent population regulation?

A) A contagious disease sweeps through a dense population of squirrels but leaves a less dense population relatively untouched.
B) Predators of lemmings search widely for places where lemmings are abundant and concentrate their hunting in those areas.
C) An outbreak of a moth species leads to a depletion of the food supply. As a result, the next generation of moths is underfed and produces few offspring.
D) When lemmings are abundant, arctic foxes switch from a primary diet of mice to a primary diet of lemmings.
E) An early cold spell kills 80 percent of the sparrows in a particular area.