A company wants to implement authentication for its new REST service using Amazon API Gateway. To authenticate the calls, each request must include HTTP headers with a client ID and user ID. These credentials must be compared to authentication data in an Amazon DynamoDB table.
What MUST the company do to implement this authentication in API Gateway?

A. Implement an AWS Lambda authorizer that references the DynamoDB authentication table
B. Create a model that requires the credentials, then grant API Gateway access to the authentication table
C. Modify the integration requests to require the credentials, then grant API Gateway access to the authentication table
D. Implement an Amazon Cognito authorizer that references the DynamoDB authentication table