strategy to enable an option for power users

[Song Su]

My application is available for about 200 users on the network. I want to
have an option button on my main form enabled to only about 50 of the 200
users. All users are already authenticated through network and I do not want
additional password for my appliction.

What's the best strategy for these 50 power users? I can put them in a table
but how to enable that option based on the presence of the record in that
table?

Thanks.