Explanation

Global infrastructure is the correct answer because:

• AWS has a global network of Availability Zones and Edge Locations distributed worldwide
• This infrastructure allows content to be served from locations closest to end users, reducing latency
• Services like Amazon CloudFront (CDN) and AWS Global Accelerator leverage this global infrastructure to optimize performance

Why other options are incorrect:

• Pay as-you-go pricing: This is about cost optimization, not performance
• Managed services: These reduce operational overhead but don't directly address latency
• Economy of scale: This refers to cost benefits from AWS's large infrastructure, not latency reduction

AWS's global infrastructure with multiple regions and edge locations ensures low latency by serving content from geographically proximate locations to users worldwide.