Explanation/Reference:
Explanation:
Scenario:
Mobile Apps: Event-triggered alerts must be pushed to mobile apps by using a custom Node.js script.

The service level agreement (SLA) for the solution requires an uptime of 99.9%

If you are already using Azure Storage Blobs or Tables and you start using queues, you are guaranteed
99.9% availability. If you use Blobs or Tables with Service Bus queues, you will have lower availability.
Note: Microsoft Azure supports two types of queue mechanisms: Azure Queues and Service Bus Queues.
Azure Queues, which are part of the Azure storage infrastructure, feature a simple REST- based Get/

Put/Peek interface, providing reliable, persistent messaging within and between services.
Service Bus queues are part of a broader Azure messaging infrastructure that supports queuing as well

as publish/subscribe, Web service remoting, and integration patterns.
References: https://msdn.microsoft.com/en-us/library/azure/hh767287.aspx