What is the AWS Well-Architected Framework primarily used for?

Correct answer: Designing cloud architectures based on best practices

Option D is correct because the AWS Well-Architected Framework is a set of architectural best practices organized into six pillars (Operational Excellence, Security, Reliability, Performance Efficiency, Cost Optimization, and Sustainability) used to evaluate and improve cloud architectures. Option A is incorrect because managing IAM policies is a specific identity and access management task, not the purpose of the Well-Architected Framework, though security is one of its pillars. Option B is incorrect because quickly launching EC2 instances is an operational activity, not what the Well-Architected Framework is designed for. Option C is incorrect because while the Cost Optimization pillar addresses cost, the Well-Architected Framework's primary purpose is holistic architecture review across all six pillars, not solely cost reduction.