Which EC2 instance type is best suited for memory-intensive workloads?

Correct answer: R-type instances

Option A is correct because AWS R-type instances (e.g., R5, R6g) are specifically designed for memory-intensive workloads such as high-performance databases, in-memory caches, and real-time big data analytics, offering a high ratio of RAM to vCPU. Option B is wrong because C-type instances are compute-optimized, suited for CPU-intensive tasks like batch processing and high-performance computing, not memory-intensive workloads. Option C is wrong because M-type instances are general-purpose with a balanced ratio of compute, memory, and networking, making them a poor fit when memory is the primary bottleneck. Option D is wrong because T-type instances are burstable general-purpose instances designed for workloads with variable CPU usage, not sustained memory-intensive operations.