AWS Certified Cloud Practitioner Practice Test 8

Reservations provide you with greater discounts, up to 75%, by paying for capacity ahead of time. Some of the servies you can reserve include: EC2, DynamoDB, ElastiCache, RDS, and RedShift.

You cannot reserve Amazon S3, you pay for what you use

AWS Lambda is a service that provides functions and cannot be reserved.

You cannot reserve Amazon CloudWatch which is a monitoring service.

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