Which is not a major similarity or difference between freshwater and marine ecosystems?
a.
both support a large number of plants and animals adapted for aquatic living
b.
ocean and freshwater system conditions generally remain constant throughout the year
c.
freshwater ecosystems have a very low salt concentration, and include ponds, lakes, streams, wetlands, and rivers
d.
saltwater ecosystems have a high salt concentration and include oceans, coral reefs, and estuaries