Which of the following formed sometime later

Options

A. oxygen and hydrogen
B. hydrogen and helium
C. carbon dioxide and oxygen
D. methane and hydrogen

Answer

To solve the question "Which of the following formed sometime later," we need to analyze the components of the early atmosphere and identify which gases formed later in the evolutionary timeline.

### Step-by-Step Solution:

1. **Understanding Early Atmosphere Composition**:
- The early atmosphere primarily consisted of gases like hydrogen (H2), ammonia (NH3), methane (CH4), and water vapor (H2O).

2. **Identifying Later Formed Gases**:
- The question asks for gases that formed later in the atmosphere. It is known that oxygen (O2) and carbon dioxide (CO2) were not present in significant amounts in the early atmosphere and formed later due to various biological and geological processes.

3. **Evaluating the Options**:
- **Option A: Oxygen and Hydrogen**: While oxygen is correct, hydrogen was present in the early atmosphere, so this option is incorrect.
- **Option B: Hydrogen and Helium**: Both of these gases were part of the early atmosphere. Thus, this option is incorrect.
- **Option C: Carbon Dioxide and Oxygen**: Both of these gases formed later in the atmosphere, making this option correct.
- **Option D: Methane and Hydrogen**: Both of these gases were present in the early atmosphere, so this option is incorrect.

4. **Conclusion**:
- The correct answer is **Option C: Carbon Dioxide and Oxygen**, as these gases formed sometime later in the atmospheric evolution.

### Final Answer:
**Option C: Carbon Dioxide and Oxygen**

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