A Company Used AWS CloudFormation to Deploy a Three-Tier Web

A company used AWS CloudFormation to deploy a three-tier web application that stores data in an Amazon RDS MySQL Multi-AZ DB instance. A DevOps Engineer must upgrade the RDS instance to the latest major version of MySQL while incurring minimal downtime. How should the Engineer upgrade the instance while minimizing downtime?

A) Update the EngineVersion property of the AWS::RDS::DBInstance resource type in the CloudFormation template to the latest desired version. Launch a second stack and make the new RDS instance a read replica. Update the EngineVersion property of the AWS::RDS::DBInstance resource type in the CloudFormation template to the latest desired version. Launch a second stack and make the new RDS instance a read replica.
B) Update the DBEngineVersion property of the AWS:: RDS::DBInstance resource type in the CloudFormation template to the latest desired version. Perform an Update Stack operation. Create a new RDS Read Replicas resource with the same properties as the instance to be upgraded. Perform a second Update Stack operation. DBEngineVersion AWS:: RDS::DBInstance resource type in the CloudFormation template to the latest desired version. Perform an Update Stack operation. Create a new RDS Read Replicas resource with the same properties as the instance to be upgraded. Perform a second operation.
C) Update the DBEngineVersion property of the AWS::RDS::DBInstance resource type in the CloudFormation template to the latest desired version. Create a new RDS Read Replicas resource with the same properties as the instance to be upgraded. Perform an Update Stack operation. resource type in the CloudFormation template to the latest desired version. Create a new RDS Read Replicas resource with the same properties as the instance to be upgraded. Perform an operation.
D) Update the EngineVersion property of the AWS::RDS::DBInstance resource type in the CloudFormation template to the latest version, and perform an Update Stack operation. resource type in the CloudFormation template to the latest version, and perform an