Rocky mountain revolution took place after

Options

A. Cenozoic era
B. Mesozoic era
C. Palaeozoic era
D. Proterozoic era

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks when the Rocky Mountain Revolution took place in relation to different geological eras.

2. **Identify Key Events**: The Rocky Mountain Revolution involved significant geological changes, including the elevation and disturbance of rocks in the Rocky Mountain region.

3. **Determine the Timeframe**: The Rocky Mountain Revolution occurred during the transition from the Cretaceous period to the Miocene period.

4. **Relate to Geological Eras**: The Cretaceous period is part of the Mesozoic Era, which is the era that comes before the Cenozoic Era.

5. **Conclusion**: Since the Rocky Mountain Revolution occurred after the Cretaceous period, it took place after the Mesozoic Era.

6. **Select the Correct Option**: Therefore, the correct answer is Option B, which states that the Rocky Mountain Revolution took place after the Mesozoic Era.

**Final Answer**: The Rocky Mountain Revolution took place after the Mesozoic Era.

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