You need to use Application Insights to monitor your canvas app. You provision an Application Insights resource in the Azure portal. 
What do you need to provide to the canvas app to stream data to Application Insights?

Answer options:

A.Connection string
B.Azure Subscription ID
C.Endpoint URL
D.Instrumentation key
E.Shared Access Signature (SAS)

Correct Answer: D 
Application Insights is the feature of Azure Monitor. It can help makers and developers to collect and analyze the canvas app telemetry. Application Insights provides information like the number of sessions, number of the logged events, number of app users. 
Developers can even trace the app`s event executions by incorporating the Trace command within the app`s code. 
Then they can work with Azure Logs and Kusto to analyze the Trace output. Or makers and developers might use Power BI for a visual representation of the Trace results. 
Before analyzing the results, you need to provision a new Application Insights resource in Azure Portal. After creating the new resource, you find and copy the Instrumentation key on the Application Insights’ Overview panel. 

This key is the link between your canvas app and Application Insights. When you open your canvas app for editing and select the App object in a Tree view, you will see the Instrumentation key field on the right App properties panel. After you paste the key, save and publish the canvas app. Whenever somebody plays the app, the Power Platform sends the telemetry to the Application Insights. 

All other options are incorrect. 
For more information about integrating the Application Insights with canvas apps, please visit the below URLs: 

https://docs.microsoft.com/en-us/powerapps/maker/canvas-apps/application-insights
https://powerapps.microsoft.com/en-us/blog/log-telemetry-for-your-apps-using-azure-application-insights/