Teacher: This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.
Teacher: Now, understand the problem? If you are still confused, see the following example:
Passage: The French and Indian War (17541763) was the North American theater of the worldwide Seven Years' War. The war was fought between the colonies of British America and New France, with both sides supported by military units from their parent countries of Great Britain and France, as well as Native American allies. At the start of the war, the French North American colonies had a population of roughly 60,000 European settlers, compared with 2 million in the British North American colonies. The outnumbered French particularly depended on the Indians. Long in conflict, the metropole nations declared war on each other in 1756, escalating the war from a regional affair into an intercontinental conflict. Question: When was the French and Indian War?
Solution: 1754-1763
Reason: It is a common convention to write (start year-end year) beside a historical event to understand when the event happened. We can observe a similar notation from the passage to conclude that the French and Indian War happened during 17541763. Therefore, the answer is 17541763.

Now, solve this instance: Passage: Far from being a mere "stopgap" pope, to great excitement, John XXIII called for an ecumenical council fewer than ninety years after the First Vatican Council (Vatican I's predecessor, the Council of Trent, had been held in the 16th century). This decision was announced on 29 January 1959 at the Basilica of Saint Paul Outside the Walls. Cardinal Giovanni Battista Montini, who later became Pope Paul VI, remarked to Giulio Bevilacqua that "this holy old boy doesn't realise what a hornet's nest he's stirring up". From the Second Vatican Council came changes that reshaped the face of Catholicism: a comprehensively revised liturgy, a stronger emphasis on ecumenism, and a new approach to the world. Question: What did John XXIII call for?
Student:
an ecumenical council