When i try to create a App Store and Ad Hoc distribution option, its disabled in my apple account, where sometimes iOS App Development option also disabled.How to create a distribution certificate .Can any one please help me?
You have reached to the limit of maximum number of "Ad Hoc Distribution Certificates" which is 3. To create new one you must revoke an old one.
For Development certificate the limit is 2 and for Production certificate the limit is 3
You don't need an individual Ad Hoc Distribution Certificate for each individual app you make. In other words, you can use the same Ad Hoc Distribution Certificate for multiple apps. The Ad Hoc Distribution Certificates, simply put, is a way for Apple to recognize and verify that your computer is a paid developer's computer.
来源：https://stackoverflow.com/questions/17444086/app-store-and-ad-hoc-disabled