A DevOps engineering wants to build an application implementation based on the CI/CD pipeline model. Which service should be used to provide hosted continuous service for open and private projects?

Ansible is an automation engine primarily used for configuration management and deployment, not a hosted continuous integration service.

pyTFS is a Python API for interacting with Team Foundation Server (TFS), not a standalone hosted CI service.

GitLab CLI is a command-line interface tool for GitLab, which offers integrated CI/CD, but the CLI itself is not the hosted CI service.

Travis CI is a hosted, distributed continuous integration service used to build and test software projects primarily hosted on GitHub and Bitbucket, supporting both open source and private repositories. It automatically builds and tests code changes, making it ideal for CI/CD pipelines.