Your application stores customers’ content in a Cloud Storage bucket, with each object being encrypted with the customer's encryption key. The key for each object in Cloud Storage is entered into your application by the customer. You discover that your application is receiving an HTTP 4xx error when reading the object from Cloud Storage. What is a possible cause of this error?

A. You attempted the read operation on the object with the customer's base64-encoded key. B. You attempted the read operation without the base64-encoded SHA256 hash of the encryption key. C. You entered the same encryption algorithm specified by the customer when attempting the read operation. D. You attempted the read operation on the object with the base64-encoded SHA256 hash of the customer's key.