Passive voice refers to an action that is being done to a subject. Active voices refers to an action that the object is doing. So your converted sentence would be "How was that word written?" Since you are talking about something being done to an object.
Answer: A. the portion of the country who quietly supported the war.
President Nixon referred to the "Silent Majority" in some of his political speeches. This was the name he gave to the part of the population that did not support the anti-war protests. They constituted the every-day American citizens, who were not particularly vocal about their political preferences, but secretly supported the war. His campaign strategy was successful, as this "silent majority" greatly contributed to his victory.