Answer - B.
The AWS Documentation mentions the following.
You can reduce the load on your source DB instance by routing read queries from your applications to the read replica.
Read replicas allow you to elastically scale out beyond the capacity constraints of a single DB Instance for read-heavy database workloads.
Option A is incorrect because the RDS database cannot be the origin of a CloudFront distribution.
Option C is incorrect because changing the database type is not the ideal approach.
Option D is incorrect because Multi-AZ is used for fault-tolerant scenarios for the database.
For more information on Read Replicas, please refer to the below URL-
https://aws.amazon.com/rds/details/read-replicas/
The best solution to decrease response time for the application is to enable Read Replicas for the database. Read Replicas allow for read-only copies of the primary RDS instance, which can be used to offload read traffic from the primary instance. This can decrease response times by reducing the load on the primary instance, which can then focus on serving write requests.
CloudFront distribution is a content delivery network (CDN) service that can cache static and dynamic content to reduce the latency of content delivery. However, it is not a suitable solution for reducing response time for database read queries as it does not interact with databases.
DynamoDB is a NoSQL database service that can handle high-velocity workloads, and it is ideal for applications with large amounts of unstructured data. While DynamoDB can be a solution to handle high read queries, it is not a direct solution to the problem, as it requires changing the database architecture.
Multi-AZ is a feature that provides high availability for RDS databases. When Multi-AZ is enabled, a standby instance is provisioned in a different availability zone, which is kept in sync with the primary instance. In case of a primary instance failure, the standby instance can take over. Although it improves availability, it does not directly decrease response time for read queries.
In summary, the best solution to decrease the response time for the application with a high volume of read queries is to enable Read Replicas for the RDS database.
