Answer:
The answer to the question "How many of the processes result in the release of oxygen into the atmosphere?" is only one of them does it: photosynthesis.
Step-by-step explanation:
The photosynthesis occurs mostly inside plants. During this process, the plant needs carbon dioxide, light and water in order to release oxygen into the atmosphere.
The respiration is a process where oxygen is consumed and carbon dioxide is released into the atmosphere.
The combustion involves two participants: a fuel and an oxidizer. During this process, oxygen is consumed too and new chemical substances are created. Also, it generates heat during the process.
The polymerization is a process where simple molecules form chains and become more complex and bigger molecules. There are different types of this reaction and some of them use oxygen when they are forming bigger molecules. To conclude, this process do not release oxygen into the atmosphere.
The nitrification is a process that is made mainly by bacteria. During this process, those organisms need to use oxygen from the environment to be able to transform ammonia to nitrate. This is an important step to enrich the soil, but it do not release oxygen.
The industrial fixation is not a natural process. During this synthetic reaction, atmospheric nitrogen is transformed into nitrogen oxides or ammonium ions that bacteria can use in nitrification. It consumes oxygen too.