Which of the following groups contain only biodegradable items? a. Grass, flowers and leather b. Grass, wood and plastic c. Fruit peels, cake and lime juice d. Cake, wood and grass

a) Grass, flowers and leather
c) Fruit peels, cake and lime juice
d) Cake, wood and grass

The groupings that contain exclusively biodegradable things are the most important. That group cannot be deemed biodegradable because plastic is not a biodegradable substance.