Answer: On-Demand

Since the requirement is just for 3 months, then the best cost effective option is to use On-Demand Instances. **Key Points:** - **Spot Instances** are for fault-tolerant, flexible workloads and can be interrupted - **Reserved Instances** (both No Upfront and Partial Upfront) require 1-3 year commitments and are cost-effective for long-term usage - **On-Demand Instances** provide maximum flexibility with no long-term commitment, making them ideal for short-term development and test environments - For a 3-month duration, On-Demand offers the best balance of cost and flexibility without the commitment of Reserved Instances

Author: Ritesh Yadav