Which entity has the power to determine the appeal and outcome of a taxpayer protest?

The correct answer is the Appraisal Review Board (ARB) because it is the designated entity responsible for handling taxpayer protests regarding property tax appraisals in Texas. The ARB is established in each appraisal district and is tasked with reviewing and resolving disputes between taxpayers and the appraisal district concerning property valuations and exemptions.

The ARB conducts hearings where taxpayers can present evidence and arguments regarding their property assessments, and it has the authority to make decisions on those appeals. The board's decisions can significantly impact the final assessed value of properties, which in turn affects the amount of property taxes owed by the taxpayer.

Other entities listed do not have the authority to determine the outcomes of taxpayer protests. The State Tax Office primarily oversees regulations and compliance related to state taxes but does not get involved in individual taxpayer disputes at the local level. The County Commissioner’s Court generally oversees broader county governance and budget issues, and while it may have some involvement in tax matters, it does not handle individual tax protests. Local Boards of Appeals do not exist in Texas property tax law, as the ARB serves this function. This distinctive role of the ARB clarifies its essential position in the property tax assessment process.