How Do I remove an Item from a category rather than deleting it.

I have Category A, B and C. Category A hold all the pool of Persons, Category B holds Persons with More than 45years of age and Category C holds persons with 44 years and below. I want to remove Persons from either Category B or C and append them back to the general list in Category A. Ideas??
1 answers

In a microflow, change Person, Select association, tick Remove to remove things from this list. Ofcourse first retrieve the object to remove and pass that as a parameter.