HOTSPOT
You have four on-premises Microsoft SQL Server data sources as described in the following table.
You plan to create three Azure data factories that will interact with the data sources as described in the
following table
You need to deploy Microsoft Data Management Gateway to support the Azure Data Factory deployment. The
solution must use new servers to host the instances of Data Management Gateway.
What is the minimum number of new servers and date management gateways you should you deploy? To
answer, select the appropriate options in the answer area.
NOTE: Each correct selection is worth one point.
Hot Area:
Answer: 
Explanation:
Box 1: 3
Box 2: 3
Considerations for using gateway
A single instance of Data Management Gateway can be used for multiple on-premises data sources.
However, a single gateway instance is tied to only one Azure data factory and cannot be shared with
another data factory.
You can have only one instance of Data Management Gateway installed on a single machine. Suppose, you
have two data factories that need to access on-premises data sources, you need to install gateways on two
on-premises computers. In other words, a gateway is tied to a specific data factory.
https://docs.microsoft.com/en-us/azure/data-factory/data-factory-data-management-gateway