Which tool can be used to request an increase in AWS service limits?

The AWS Support Center is the correct tool for requesting an increase in AWS service limits. When users need additional resources beyond the default limits set by AWS for various services, the Support Center provides the necessary interface for submitting these requests. Users can specify the service for which they need increased limits and provide any required justification for the request, making it straightforward to escalate these needs to AWS support.

Other options do not fulfill this specific purpose. The AWS Management Console provides a user-friendly interface for managing AWS resources but does not directly facilitate limit increase requests. The AWS Command Line Interface allows for resource management and operations through commands, but it also lacks the specific functionality for submitting limit increases. AWS Budgets is a financial management tool designed for tracking cost and usage against a specified budget, rather than managing service limits.