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: Who wanted the Russian army to negotiate peace?, Context: The Russian army withdrew and retreated past Moscow. Napoleon entered the city, assuming its fall would end the war and Alexander would negotiate peace. However, on orders of the city's governor Feodor Rostopchin, rather than capitulation, Moscow was burned. After five weeks, Napoleon and his army left. In early November Napoleon got concerned about loss of control back in France after the Malet coup of 1812. His army walked through snow up to their knees and nearly 10,000 men and horses froze to death on the night of 8/9 November alone. After Battle of Berezina Napoleon succeeded to escape but had to abandon much of the remaining artillery and baggage train. On 5 December, shortly before arriving in Vilnius, Napoleon left the army in a sledge.
Example Output: Napoleon

Example Input: What would an engine driver have to do to adjust the more modern type of valve?, Context: Steam engines frequently possess two independent mechanisms for ensuring that the pressure in the boiler does not go too high; one may be adjusted by the user, the second is typically designed as an ultimate fail-safe. Such safety valves traditionally used a simple lever to restrain a plug valve in the top of a boiler. One end of the lever carried a weight or spring that restrained the valve against steam pressure. Early valves could be adjusted by engine drivers, leading to many accidents when a driver fastened the valve down to allow greater steam pressure and more power from the engine. The more recent type of safety valve uses an adjustable spring-loaded valve, which is locked such that operators may not tamper with its adjustment unless a seal illegally is broken. This arrangement is considerably safer.[citation needed]
Example Output: seal illegally is broken

Example Input: What do T cells secrete into their environment?, Context: A B cell identifies pathogens when antibodies on its surface bind to a specific foreign antigen. This antigen/antibody complex is taken up by the B cell and processed by proteolysis into peptides. The B cell then displays these antigenic peptides on its surface MHC class II molecules. This combination of MHC and antigen attracts a matching helper T cell, which releases lymphokines and activates the B cell. As the activated B cell then begins to divide, its offspring (plasma cells) secrete millions of copies of the antibody that recognizes this antigen. These antibodies circulate in blood plasma and lymph, bind to pathogens expressing the antigen and mark them for destruction by complement activation or for uptake and destruction by phagocytes. Antibodies can also neutralize challenges directly, by binding to bacterial toxins or by interfering with the receptors that viruses and bacteria use to infect cells.
Example Output:
lymphokines