Unless your app is using some special encryption you can simply add Boolean a key to your
Info.plist with name
ITSAppUsesNonExemptEncryption and value
If your app is using custom encryption then you will need to provide extra legal documents and go through a review of your encryption before being able to select builds.
If you continue with selecting that version for testing, it will ask for the compliance information manually. Choosing "No" presents you with the plist recommendation above.
This is change has been announced in the 2015 WWDC, but I guess it has been enforced only very recently. See this and this for a transcript of the WWDC session related to the export compliance, just to a text search for "export".
There are other similar questions on SO, see:
~ Answered on 2016-03-07 11:19:53