Which Event or Condition Is a Density-Independent Factor That Could

Which event or condition is a density-independent factor that could influence population growth?

A) a disease that spreads through direct physical contact
B) a new predator that moves into an area with hunting tactics that the prey species are not adapted to avoid
C) a volcanic eruption that covers an island in a layer of lava
D) a sudden decrease in the food supply due to usually dry conditions
E) all of these