iOS Question my app with iadmob cannot publish to appstore

apple ask me about IDFA, I didn't know about this, when I choose 'no'(
Does this app use the Advertising Identifier (IDFA)?)
.it alerts that "Your app is using the Advertising Identifier (IDFA). You must either provide details about the IDFA usage or remove it from the app and submit your binary again."

when I choose 'yes'.I must select some options(1-3)
****************
If your app is using the Advertising Identifier, check your code—including any third-party code—before you submit it to make sure that your app uses the Advertising Identifier only for the purposes listed below and respects the Limit Ad Tracking setting. If you include third-party code in your app, you are responsible for the behavior of such code, so be sure to check with your third-party provider to confirm compliance with the usage limitations of the Advertising Identifier and the Limit Ad Tracking setting.
This app uses the Advertising Identifier to (select all that apply):
1.Serve advertisements within the app
2.Attribute this app installation to a previously served advertisement
3.Attribute an action taken within this app to a previously served advertisement
*****************

I try and try but I cannot publish app
help me,please