HOTSPOT
You are designing a SQL Server Integration Services (SSIS) package configuration strategy.
The package configuration must meet the following requirements:
Include multiple properties in a configuration.
Force packages to load all settings in the configuration.
Support Encrypting File System (EFS) formats.
You need to select the appropriate configuration.
Which configuration type should you use?
To answer, select the appropriate option from the drop-down list in the dialog box.
Answer: 
Explanation:
SQL Server. XML doesn’t support encryption
Changed my mind. I will go with the answer – XML configuration file
I think the EFS line is there to tell you that you need to use the file system
Panos is ultimately right: it should be XML
XML configuration