A company is planning on building a mobile application. The data for the application from various users needs to be stored in a data store that is highly available. The data store should scale on demand and the right authentication mechanism should be in place for the mobile application. Which of the following can help fulfil these requirements? Choose 2 answers from the options given below

Answer options:

A.Make the application store its data on EBS volumes attached to EC2 Instances
B.Make the application store its data on S3
C.Make the application users authenticate with IAM Access Keys
D.Use the AWS Cognito service for authentication

Answer – B and D
The AWS Documentation mentions the following
Companies today need the ability to simply and securely collect, store, and analyze their data at a massive scale. Amazon S3 is object storage built to store and retrieve any amount of data from anywhere – web sites and mobile apps, corporate applications, and data from IoT sensors or devices. It is designed to deliver 99.999999999% durability, and stores data for millions of applications used by market leaders in every industry. 
Amazon Cognito provides authentication, authorization, and user management for your web and mobile apps. Your users can sign in directly with a user name and password, or through a third party such as Facebook, Amazon, or Google.
Option A is incorrect since this is not a durable and highly available data store
Option C is incorrect since this is not a secure way to grant access
For more information on AWS Cognito and S3, please visit the url
https://aws.amazon.com/s3/