The user accounts are synced from the on-premise Active Directory to the Microsoft Azure Active Directory (Azure AD). Therefore, the city attribute must be changed in the on-premise Active Directory.
You can use Windows PowerShell on a domain controller and run the Get-ADUser cmdlet to get the required users and pipe the results into Set-ADUser cmdlet to modify the city attribute.
Note:
There are several versions of this question in the exam. The question has two possible correct answers:
1. From Windows PowerShell on a domain controller, run the Get-ADUser and Set-ADUser cmdlets.
2. From Active Directory Administrative Center, select the Active Directory users, and then modify the Properties settings.
Other incorrect answer options you may see on the exam include the following:
1. From the Azure portal, select all the Azure AD users, and then use the User settings blade.
2. From Windows PowerShell on a domain controller, run the Get-AzureADUser and Set-AzureADUser cmdlets.
3. From the Microsoft 365 admin center, select the users, and then use the Bulk actions option.
4. From Azure Cloud Shell, run the Get-ADUser and Set-ADUser cmdlets.
Reference:
https://docs.microsoft.com/en-us/powershell/module/addsadministration/set-aduser