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.

Ex Input:
Passage: During the Second World War, General Dornberger was the military head of the army's rocket program, Zanssen became the commandant of the Peenemunde army rocket centre, and von Braun was the technical director of the ballistic missile program. They would lead the team that built the Aggregate-4 (A-4) rocket, which became the first vehicle to reach outer space during its test flight program in 1942 and 1943. By 1943, Germany began mass-producing the A-4 as the Vergeltungswaffe 2 ("Vengeance Weapon" 2, or more commonly, V2), a ballistic missile with a 320 kilometers (200 mi) range carrying a 1,130 kilograms (2,490 lb) warhead at 4,000 kilometers per hour (2,500 mph). Its supersonic speed meant there was no defense against it, and radar detection provided little warning. Germany used the weapon to bombard southern England and parts of Allied-liberated western Europe from 1944 until 1945. After the war, the V-2 became the basis of early American and Soviet rocket designs. Question: What was von Braun's role in the army's rocket program during during World War II?

Ex Output:
technical director of the ballistic missile program

Ex Input:
Passage: In the mid-1950s, Frank Burnet, inspired by a suggestion made by Niels Jerne, formulated the clonal selection theory (CST) of immunity. On the basis of CST, Burnet developed a theory of how an immune response is triggered according to the self/nonself distinction: "self" constituents (constituents of the body) do not trigger destructive immune responses, while "nonself" entities (e.g., pathogens, an allograft) trigger a destructive immune response. The theory was later modified to reflect new discoveries regarding histocompatibility or the complex "two-signal" activation of T cells. The self/nonself theory of immunity and the self/nonself vocabulary have been criticized, but remain very influential. Question: What property of T cells caused modification of CST?

Ex Output:
the complex "two-signal" activation

Ex Input:
Passage: A political party is typically led by a party leader (the most powerful member and spokesperson representing the party), a party secretary (who maintains the daily work and records of party meetings), party treasurer (who is responsible for membership dues) and party chair (who forms strategies for recruiting and retaining party members, and also chairs party meetings). Most of the above positions are also members of the party executive, the leading organization which sets policy for the entire party at the national level. The structure is far more decentralized in the United States because of the separation of powers, federalism and the multiplicity of economic interests and religious sects. Even state parties are decentralized as county and other local committees are largely independent of state central committees. The national party leader in the U.S. will be the president, if the party holds that office, or a prominent member of Congress in opposition (although a big-state governor may aspire to that role). Officially, each party has a chairman for its national committee who is a prominent spokesman, organizer and fund-raiser, but without the status of prominent elected office holders. Question: Who is responsible for the membership fees and expenses?

Ex Output:
party treasurer