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

Example Input: What did the land bridge between the Americas cause to change?, Context: South America became linked to North America through the Isthmus of Panama during the Pliocene, bringing a nearly complete end to South America's distinctive marsupial faunas. The formation of the Isthmus had major consequences on global temperatures, since warm equatorial ocean currents were cut off and an Atlantic cooling cycle began, with cold Arctic and Antarctic waters dropping temperatures in the now-isolated Atlantic Ocean. Africa's collision with Europe formed the Mediterranean Sea, cutting off the remnants of the Tethys Ocean. Sea level changes exposed the land-bridge between Alaska and Asia. Near the end of the Pliocene, about 2.58 million years ago (the start of the Quaternary Period), the current ice age began. The polar regions have since undergone repeated cycles of glaciation and thaw, repeating every 40,000–100,000 years.
Example Output: global temperatures

Example Input: What happened to Santa Pudenziana?, Context: With the building of Christian basilicas in the late 4th century, wall and ceiling mosaics were adopted for Christian uses. The earliest examples of Christian basilicas have not survived, but the mosaics of Santa Constanza and Santa Pudenziana, both from the 4th century, still exist. The winemaking putti in the ambulatory of Santa Constanza still follow the classical tradition in that they represent the feast of Bacchus, which symbolizes transformation or change, and are thus appropriate for a mausoleum, the original function of this building. In another great Constantinian basilica, the Church of the Nativity in Bethlehem the original mosaic floor with typical Roman geometric motifs is partially preserved. The so-called Tomb of the Julii, near the crypt beneath St Peter's Basilica, is a 4th-century vaulted tomb with wall and ceiling mosaics that are given Christian interpretations. The Rotunda of Galerius in Thessaloniki, converted into a Christian church during the course of the 4th century, was embellished with very high artistic quality mosaics. Only fragments survive of the original decoration, especially a band depicting saints with hands raised in prayer, in front of complex architectural fantasies.
Example Output: The Rotunda of Galerius in Thessaloniki

Example Input: At what point was the key river on the continent controlled?, Context: The Byzantine Empire ruled the northern shores of the Sahara from the 5th to the 7th centuries. After the Muslim conquest of Arabia (Arabian peninsula) the Muslim conquest of North Africa began in the mid-7th to early 8th centuries, Islamic influence expanded rapidly on the Sahara. By the end of 641 all of Egypt was in Muslim hands. The trade across the desert intensified. A significant slave trade crossed the desert. It has been estimated that from the 10th to 19th centuries some 6,000 to 7,000 slaves were transported north each year.
Example Output:
By the end of 641