According to Oparin , the primitive atmosphere of the Earth is ?

Options

A. Reduced
B. Without oxygen
C. Oxidized
D. Both (a) and (b)

Answer

To solve the question regarding Oparin's view of the primitive atmosphere of the Earth, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Oparin's Hypothesis**:
- Oparin proposed a theory about the origin of life on Earth, which included details about the primitive atmosphere.

2. **Characteristics of the Primitive Atmosphere**:
- According to Oparin, the primitive atmosphere was composed of various gases, primarily hydrogen, ammonia, methane, and water vapor, but it lacked free oxygen.

3. **Defining 'Reduced' Atmosphere**:
- A 'reduced' atmosphere is one that has a low concentration of oxygen. In this context, it means that the atmosphere was conducive to the formation of organic compounds, as there was no free oxygen to react with these compounds.

4. **Conclusion about Oxygen Levels**:
- Since Oparin's theory states that there was no free oxygen in the primitive atmosphere, it confirms that the atmosphere was indeed 'without oxygen'.

5. **Selecting the Correct Answer**:
- The options given are:
a. Reduced
b. Without oxygen
c. Oxidized
d. Both a and b
- Since the atmosphere was both reduced and without oxygen, the correct answer is option D: both A and B.

### Final Answer:
The primitive atmosphere of the Earth, according to Oparin, is both reduced and without oxygen (Option D).

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