In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

Let me give you an example: what is the first event mentioned?, Context: The Russian Revolution is the series of revolutions in Russia in 1917, which destroyed the Tsarist autocracy and led to the creation of the Soviet Union. Following the abdication of Nicholas II of Russia, the Russian Provisional Government was established. In October 1917, a red faction revolution occurred in which the Red Guard, armed groups of workers and deserting soldiers directed by the Bolshevik Party, seized control of Saint Petersburg (then known as Petrograd) and began an immediate armed takeover of cities and villages throughout the former Russian Empire.
The answer to this example can be: Russian Revolution
Here is why: This is a good example, and the Russian Revolution is the first event mentioned.

OK. solve this:
Which happened later, the late 11th century, or the Concordat of Worms?, Context: Monastic reform inspired change in the secular church. The ideals that it was based upon were brought to the papacy by Pope Leo IX (pope 1049–1054), and provided the ideology of the clerical independence that led to the Investiture Controversy in the late 11th century. This involved Pope Gregory VII (pope 1073–85) and Emperor Henry IV, who initially clashed over episcopal appointments, a dispute that turned into a battle over the ideas of investiture, clerical marriage, and simony. The emperor saw the protection of the Church as one of his responsibilities as well as wanting to preserve the right to appoint his own choices as bishops within his lands, but the papacy insisted on the Church's independence from secular lords. These issues remained unresolved after the compromise of 1122 known as the Concordat of Worms. The dispute represents a significant stage in the creation of a papal monarchy separate from and equal to lay authorities. It also had the permanent consequence of empowering German princes at the expense of the German emperors.
Answer:
the Concordat of Worms