The externaldata () function can be used access data stored on an Azure Blob for looking up a dynamic list.

Answer options:

A.True
B.False

Correct Answer: A
Option A is correct. The externaldata operator returns a table whose schema is defined in the query itself, and whose data is read from an external storage artifact, such as a blob in Azure Blob Storage or a file in Azure Data Lake Storage.
Reference: 

https://docs.microsoft.com/en-us/azure/data-explorer/kusto/query/externaldata-operator?pivots=azuredataexplorer