Biotic factors are those that are living in an ecosystem, such as plants and animals, while abiotic factors are those that are not, such as rocks, temperature, water, sunlight, soil etc.
C is correct for number 2 because broadleaf trees are a biotic factor, while precipitation, or rainwater, is abiotic.
A is incorrect because both are biotic factors, since both are living
B is incorrect because both are abiotic factors, since both are nonliving
D is incorrect because both are biotic factors, since both are living
"Water quality" may include the amounts of dissolved oxygen
and the levels of algal growth, pollutants which may be present and the pH level. Water quality effects also which types of organisms can
survive in a body of water.
Shellfish require a high level
of dissolved oxygen and their abundance is an indication of good water quality. Shellfish are sensitive to changes in the ecosystem and they cannot easily escape changes in the water quality. These are one of the reasons why shellfish are good indicators of water quality.
This is very easy but all of the above
