Why Do Some Seeds Need to Pass Through an Animal's

Why do some seeds need to pass through an animal's digestive tract before they will germinate?

A) The warm temperatures trigger germination.
B) The alternating light and dark exposure triggers germination.
C) The seeds get wet inside the animal.
D) Digestive enzymes and strong acids make the seed coat permeable to water and oxygen.
E) The seed travels away from the parent plant before it is excreted by the animal.