The phrase describes a change that is sudden and dramatic, not gradual or small.
Step 1: Understand the meaning
- Upheaval means a violent or sudden change, like a big disruption.
- Transition means changing from one state to another, usually gradually.
- Evolution means slow and natural development over time.
- Alteration means a change, but not necessarily sudden or dramatic.
Step 2: Compare options
Only (A) Upheaval fits the idea of a sudden, dramatic event. The others imply slow or minor changes.
Step 3: Conclusion
The best word is (A) Upheaval.