Answer: Correct Answer: Second Vatican Council

Pope John XXIII convened the Second Vatican Council on October 11, 1962, with the goal of renewing and modernizing the Catholic Church to better engage with the contemporary world. Known as Vatican II, this council introduced significant changes, including the use of vernacular languages in the liturgy, a renewed emphasis on ecumenism, and a focus on the Church's role in promoting social justice and peace. Pope John XXIII's vision for the council was encapsulated in his call for "aggiornamento," meaning "bringing up to date."