picklist has multiple entries of same text

picklist has multiple entries of same text

I've got two forms.

Form A contains a text field "Person" and a text field "Business".
Form B contains a Picklist based on Form A.Person

However, within the Form B picklist, it contains multiple versions of the same FormA.Person.

I.e. Multiple records of Form A could have the same Person entered into it.
Form A, Version 1 - Person = Brent
Form A, Version 2 - Person = Brent

On Form B, Picklist choices include "Brent" two times.

How can I make it so that "Brent" is included only one time on the Picklist?