We prove that AD(R) implies the existence of a definable class function which, given a countable set X, a tall ideal omega on w containing Fin and a function from I Fin to X which is invariant under finite changes, selects a nonempty finite subset of X. Among other applications, this gives an alternate proof of the fact (previously established by Di Prisco-Todorcevic) that there is no selector for the E-0 degrees in the P(omega)/Fin-extension of a model of AD(R).
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