Which pairs of AWS and Azure services are equivalent?

EC2 = VMs, S3 = Blob Storage, Lambda = Functions, EKS = AKS (Correct option)
EC2 = Blob Storage, S3 = Azure Functions, Lambda = AKS
S3 = AKS, Lambda = Virtual Machines, EKS = Blob Storage
They have no equivalents, because each cloud is different

EC2 = Azure Virtual Machines; S3 = Blob Storage; Lambda = Azure Functions; EKS = AKS; IAM = Entra ID + Azure RBAC

Both clouds offer similar building blocks with different names:

Compute: EC2 / Virtual Machines; Lambda / Functions; EKS / AKS; Elastic Beanstalk / App Service.
Storage: S3 / Blob Storage; EBS / Managed Disks.
Databases: RDS / Azure SQL & Azure Database for PostgreSQL; DynamoDB / Cosmos DB.
Network: VPC / VNet; Security Group / NSG; Route 53 / Azure DNS; CloudFront / Azure CDN & Front Door.
Identity: IAM / Entra ID (formerly Azure AD) + Azure RBAC.
Messaging: SQS / Storage Queues or Service Bus; SNS / Event Grid.
Monitoring: CloudWatch / Azure Monitor & Application Insights.
Secrets: Secrets Manager / Key Vault. Registry: ECR / ACR.

Same ideas, different names. Learn the mapping table.