Final answer:
The user limit recommendation for pilot programs utilizing email forwarding is 50 users, while for FastTrack it is unlimited.
Step-by-step explanation:
The recommended user limit for pilot programs utilizing email forwarding is 50 users, while for pilot programs utilizing FastTrack, the user limit is unlimited. So, option c) is the correct answer choice. It is important to note that these limits are recommendations and can vary depending on the specific requirements and resources of the program.