You have been tasked to grant access to sensitive files to external auditors for a limited time period of 4 hours only. The files should not be strictly available after 4 hours. Adhering to Google best practices, how would you efficiently share the file?

A. Host a website on Compute Engine instance and expose the files using Public DNS and share the URL with the auditors. Bring down the instance after 4 hours. B. Host a website on App Engine instance and expose the files using Public DNS and share the URL with the auditors. Bring down the instance after 4 hours. C. Store the file in Cloud Storage. Generate a signed URL with 4 hours expiry and share it with the auditors. D. Store the file in Cloud Storage. Grant the allUsers access to the file share it with the auditors. Remove allUsers access after 4 hours.