The decomposition of organic compounds, in the presence of oxygen without the development of odoriferous substances , is called

Options

A. nitrification
B. `N_2` - fixation
C. decay
D. denitrification

Answer

To solve the question, we need to identify the term that describes the decomposition of organic compounds in the presence of oxygen without producing any odoriferous substances.

### Step-by-Step Solution:

1. **Understanding Decomposition**: Decomposition refers to the breakdown of organic compounds into simpler substances. This process can occur in various environments, including the presence of oxygen.

2. **Role of Oxygen**: The presence of oxygen typically indicates that the decomposition is aerobic. Aerobic decomposition is a process where organic matter is broken down by microorganisms in the presence of oxygen.

3. **Odoriferous Substances**: The question specifies that the decomposition occurs without the development of odoriferous substances. This suggests that the process is clean and does not produce foul smells, which are often associated with anaerobic decomposition or putrefaction.

4. **Identifying the Correct Term**: The term that describes the aerobic decomposition of organic matter without the production of unpleasant odors is known as "decay." Decay is a natural process that involves the breakdown of organic material by microorganisms, leading to the formation of simpler compounds.

5. **Eliminating Other Options**: The other terms mentioned (nitrification, antifixation, denitrification) are specific processes related to nitrogen compounds and do not pertain to the general decomposition of organic matter in the presence of oxygen.

6. **Conclusion**: Therefore, the correct answer to the question is "decay."

### Final Answer:
The decomposition of organic compounds, in the presence of oxygen without the development of odoriferous substances, is called **decay**.

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