Final answer:
To address an expiring token-signing certificate, Azure AD PowerShell is the appropriate tool, allowing for the renewal of the certificate and the management of Azure Active Directory settings.
Step-by-step explanation:
To deal with an expiring token-signing certificate, you would most likely use Azure AD PowerShell. This tool allows for the automation of the renewal process for the token-signing certificate. With Azure AD PowerShell, you can run commands to renew the certificate and ensure that your services remain uninterrupted. Other listed options do not specifically deal with the automation or manual process of renewing a token-signing certificate like Azure AD PowerShell does.
For example, with Azure AD PowerShell, you can use cmdlets such as Get-AzureADCertificate to view the current certificates and New-AzureADCertificate to create a new token-signing certificate. Once the new certificate has been created and designated as the primary, you can then update the federation settings, if needed, to ensure a smooth transition.