A company hosts a web application that writes to an Amazon DynamoDB table. Application users frequently observe and report errors. The development team examines Amazon CloudWatch logs and frequently sees the following error:
400 Bad Request ProvisionedThroughputExceededException
What is the cause of this error?

A. The application does not have the required permissions for the DynamoDB table.
B. The item that the application is placing on the table exceeds the item size limit.
C. The development team has not allocated enough space for the table and its indexes.
D. The development team has not allocated enough write capacity units (WCU) for the table and Its indexes.