How can I test my React components that use Axios to fetch data and specifically check for 404 error handling?

Use testing libraries like Jest and React Testing Library. Mock your Axios requests using `jest.mock('axios')` to control the response. In your tests, mock the Axios `get()` (or relevant method) to return a 404 status code with an appropriate error message. Verify that your component renders the expected error message when the mocked 404 error occurs. This allows you to ensure that your error handling logic is working correctly without actually hitting your API.