The primitive atmosphere of earth contained water vapours, hydrogen, ammonia and

Options

A. `CO_(2)`
B. Oxygen
C. Nitrogen
D. Methane

Explanation

To answer the question about the components of the primitive atmosphere of Earth, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Primitive Atmosphere**: The primitive atmosphere of Earth refers to the gaseous envelope that surrounded the planet during its early formation. This atmosphere was significantly different from the one we have today.

2. **Identifying the Components**: The question states that the primitive atmosphere contained water vapors, hydrogen, and ammonia. We need to identify the fourth component from the given options: U2, B oxygen, C nitrogen, D methane.

3. **Researching Early Atmospheric Composition**: Historical scientific research indicates that the early atmosphere was composed primarily of gases like methane (CH₄), ammonia (NH₃), water vapor (H₂O), and hydrogen (H₂). It is important to note that free oxygen (O₂) was not present in significant amounts during this time.

4. **Choosing the Correct Option**: Among the options provided:
- A: U2 (not a known atmospheric gas)
- B: Oxygen (not present in the primitive atmosphere)
- C: Nitrogen (while present, it was not one of the primary components)
- D: Methane (which is indeed one of the main components of the primitive atmosphere)

Therefore, the correct answer is **D: Methane**.

### Final Answer:
The primitive atmosphere of Earth contained water vapors, hydrogen, ammonia, and **methane**.

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