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: From what era, once thought devoid of animal life, was evidence of grazer populations discovered?, Context: Some paleontologists suggest that animals appeared much earlier than the Cambrian explosion, possibly as early as 1 billion years ago. Trace fossils such as tracks and burrows found in the Tonian period indicate the presence of triploblastic worms, like metazoans, roughly as large (about 5 mm wide) and complex as earthworms. During the beginning of the Tonian period around 1 billion years ago, there was a decrease in Stromatolite diversity, which may indicate the appearance of grazing animals, since stromatolite diversity increased when grazing animals went extinct at the End Permian and End Ordovician extinction events, and decreased shortly after the grazer populations recovered. However the discovery that tracks very similar to these early trace fossils are produced today by the giant single-celled protist Gromia sphaerica casts doubt on their interpretation as evidence of early animal evolution.
Example Output: the Tonian period

Example Input: What economic improvement did the successors make?, Context: Louis-Philippe was overthrown by a popular uprising in the streets of Paris in 1848. His successor, Napoleon III, and the newly appointed prefect of the Seine, Georges-Eugène Haussmann, launched a gigantic public works project to build wide new boulevards, a new opera house, a central market, new aqueducts, sewers, and parks, including the Bois de Boulogne and Bois de Vincennes. In 1860, Napoleon III also annexed the surrounding towns and created eight new arrondissements, expanding Paris to its current limits.
Example Output: central market

Example Input: What is the point of SODIS?, Context: Solar water disinfection (SODIS) involves exposing water-filled plastic polyethylene terephthalate (PET) bottles to sunlight for several hours. Exposure times vary depending on weather and climate from a minimum of six hours to two days during fully overcast conditions. It is recommended by the World Health Organization as a viable method for household water treatment and safe storage. Over two million people in developing countries use this method for their daily drinking water.
Example Output:
disinfection