Which AWS security service defends applications from DDoS attacks using continuous detection and automatic inline mitigation?

AWS Shield is the correct answer because it is a managed Distributed Denial of Service (DDoS) protection service that safeguards applications running on AWS. It provides always-on detection and automatic inline mitigations to minimize application downtime and latency. Amazon Inspector is an automated security assessment service that helps improve the security and compliance of applications deployed on AWS, but it does not directly defend against DDoS attacks. AWS WAF (Web Application Firewall) helps protect web applications from common web exploits (like SQL injection and cross-site scripting) that could affect application availability, compromise security, or consume excessive resources, but its primary focus is not DDoS protection. Elastic Load Balancing (ELB) distributes incoming application traffic across multiple targets, such as EC2 instances, to increase the fault tolerance and availability of applications, but it is not a dedicated DDoS protection service.