"Willy and Brogan, aged 16, enter into a written contract in which Brogan will sell his horse to Willy for $250. Before the sale is finalized, Brogan seeks to be released from the contract and wants to offer in-court oral testimony concerning his age. The admission of Brogan's testimony is most likely governed by the rule"

parol evidence

Explanation:

Based on the scenario being described it can be said that the admission of Brogan's testimony is most likely governed by the parol evidence rule. This rule created to prevent a party from introducing evidence before the agreement was made final in order to change the existing contract. Which is what Brogan is doing in this scenario by trying to release evidence about his age before the finalization of the contract.

A

Explanation:

chosen by the legislative of each state