<u>Answer;</u>
C) organic matter; rocks.
The uppermost horizon, horizon O, in this profile is composed mostly of <u>organic matter</u>, while the lower horizon, horizon C, is composed mostly of <u>rocks.</u>
<u>Explanation;</u>
-Soil contains the following major horizons, that is A B and C. Some soils may have horizon O, which may be thin or thick or even lack in some soils. This O horizon is found at the surface of many soils and normally contains organic materials at various decomposition stages. these are materials such as plants, leaves and bugs.
-C horizon is the layer that is below the B horizon. It contains larger weathered fragments or broken up-bedrock.
Neutrons
The atomic mass is the weight of the protons and neutrons in the nucleus.
The answer is; D.
This can be called a secondary ecological succession because it includes the disruption of the former ecology, rather than the ecological succession from a new environment-primary succession. The invasive species outcompete the native species in their environment. In addition, the invasive species lack a natural predator hence spread unregulated in the environment.
