What is the “correct” position for a Catholic? — I respond to a reader comment

Portion of Fra Angelico's "The Forerunners of Christ with Saints and Martyrs" (1424)

What is the “correct” position on subsidiarity, or any other issue, for a Catholic when the USCCB, the Catechism, various encyclicals, popes’ comments and the Bible don’t all agree? Which has authority? Or is there a “correct” position? I respond to a reader comment.