I'm currently uploading my App to the App Store and Apple is asking me if this app users IDFA. I'm using the latest Admob SDK or 6.8.0 and I don't know if it uses IDFA or not, and if it does which check boxes should I hit X.X
I'm having the same issue here and I was a bit afraid of checking the last box, since I have no idea what the 3rd party SDK will do with the data collected and if they will respect the Limit Ad Settings.
But I found a post by a Google Admob programmer, Eric Leichtenschlag, on their foruns:
The Google Mobile Ads SDK and the Google Conversion Tracking SDK utilize Apple's advertising identifier introduced in iOS 6 (IDFA). While each developer is responsible for how they access device data, the SDKs use IDFA under the guidelines laid out in the iOS developer program license agreement, including Limit Ad Tracking.
Including Limit Ad Tracking. This is what the last box is all about. So I guess it's all ok to check that if you use only AdMob. If you use other SDK I strongly recommend checking if they respect the guidelines as well.
Since I run only ads, I only checked the first box and the last one, which is mandatory and you must sign. App was approved and released, no issues.