Form with checkbox inventory management

Hello.
My project will require me to have a registration form with the standard fields for an event. The form will also require me to set up check boxes which for speakers at the event. When people fill out the form, they can also choose which speakers they want to attend by clicking on the check boxes.

The catch is that after the check box for Speaker “A” has been submitted 50 times, I need the check box for speaker “A” to become hidden since there are only enough room to seat 50 people.

Is there such thing as a form that can do this? If so, can you please provide me with a plugin link to the plugin?

Thank you so much.
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TLDR
I’m looking for a plugin that has the ability to make check boxes and after the certain check boxes are clicked on a certain number of times, that field will become hidden.

Is there such thing as a form that can do this? If so, can you please provide me with a plugin link to the plugin?

Thank you so much.