Answer:
Zebra mussels are spread from one body of water to another by natural flow, carried on the feathers or feet of birds, or by humans in bait buckets or on boats.
Remember that a biotic factor is a living component in an ecosystem that affects the population of another organism. So that means that the answer is B.
Answer:
Competition will occur between organisms in an ecosystem when their niches overlap, they both try to use the same resource and the resource is in short supply. Animals compete for food, water and space to live. Plants compete for light, water, minerals and root space.
