From the point of view of early chemical evolution that preceded the origin of life on earth, the most important simple organic molecules formed were

Options

A. sugars and amino acids
B. glycerol and fatty acids
C. puriness and pyrimidines
D. all of these

Explanation

To answer the question regarding the most important simple organic molecules formed during early chemical evolution that preceded the origin of life on Earth, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Chemical Evolution**:
- Chemical evolution refers to the process by which simple organic molecules formed from inorganic substances under the conditions present on early Earth. This theory was proposed by scientists Oparin and Haldane.

2. **Identifying Key Organic Molecules**:
- The early Earth had a reducing atmosphere, which lacked free oxygen and was composed mainly of gases such as methane, ammonia, water vapor, and hydrogen. Under these conditions, various simple organic molecules were synthesized.

3. **Recognizing the Importance of Biomolecules**:
- Different types of organic molecules are essential for the formation of living cells. These include:
- **Sugars and Amino Acids**: Sugars serve as energy sources, while amino acids are the building blocks of proteins.
- **Glycerol and Fatty Acids**: These are crucial for forming lipids, which are essential components of cell membranes.
- **Purines and Pyrimidines**: These nitrogenous bases are vital for the formation of nucleic acids (DNA and RNA), which carry genetic information.

4. **Evaluating the Options**:
- The question provides multiple options, including combinations of the above-mentioned molecules. Each of these groups of molecules plays a significant role in the biochemistry of living organisms.

5. **Conclusion**:
- Since all the mentioned molecules (sugars, amino acids, glycerol, fatty acids, purines, and pyrimidines) are crucial for the development of life, the correct answer is that all of these molecules formed during chemical evolution are important.

### Final Answer:
**All of these molecules formed during chemical evolution are very important.**

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