A Solutions Architect Is Implementing Infrastructure as Code for a Two-Tier

A solutions architect is implementing infrastructure as code for a two-tier web application in an AWS CloudFormation template. The web frontend application will be deployed on Amazon EC2 instances in an Auto Scaling group. The backend database will be an Amazon RDS for MySQL DB instance. The database password will be rotated every 60 days. How can the solutions architect MOST securely manage the configuration of the application's database credentials?

A) Provide the database password as a parameter in the CloudFormation template. Create an initialization script in the Auto Scaling group's launch configuration UserData property to reference the password parameter using the Ref intrinsic function. Store the password on the EC2 instances. Reference the parameter for the value of the MasterUserPassword property in the AWS::RDS::DBInstance resource using the Ref intrinsic function.
B) Create a new AWS Secrets Manager secret resource in the CloudFormation template to be used as the database password. Configure the application to retrieve the password from Secrets Manager when needed. Reference the secret resource for the value of the MasterUserPassword property in the AWS::RDS::DBInstance resource using a dynamic reference.
C) Create a new AWS Secrets Manager secret resource in the CloudFormation template to be used as the database password. Create an initialization script in the Auto Scaling group's launch configuration UserData property to reference the secret resource using the Ref intrinsic function. Reference the secret resource for the value of the MasterUserPassword property in the AWS::RDS::DBInstance resource using the Ref intrinsic function.
D) Create a new AWS Systems Manager Parameter Store parameter in the CloudFormation template to be used as the database password. Create an initialization script in the Auto Scaling group's launch configuration UserData property to reference the parameter. Reference the parameter for the value of the MasterUserPassword property in the AWS::RDS::DBInstance resource using the Fn::GetAtt intrinsic function.