A Developer created a dashboard for an application using Amazon API Gateway, Amazon S3, AWS Lambda, and Amazon RDS. The Developer needs an authentication mechanism allowing a user to sign in and view the dashboard. It must be accessible from mobile applications, desktops, and tablets, and must remember user preferences across platforms.
Which AWS service should the Developer use to support this authentication scenario?

A. AWS KMS
B. Amazon Cognito
C. AWS Directory Service
D. Amazon IAM