Step-by-step explanation:
Without additional context, it is difficult to determine what event led to Anderson's performance at the Lincoln Memorial for a crowd of 75,000 people. However, it is possible that the performance is referring to the famous concert given by contralto Marian Anderson on April 9, 1939. At the time, Anderson was one of the most celebrated singers in the world, but she was denied permission to perform at Constitution Hall in Washington D.C. due to her race. In response, First Lady Eleanor Roosevelt resigned from the Daughters of the American Revolution, which had refused to allow Anderson to perform. As a result, Anderson was invited to perform at the Lincoln Memorial instead, where she gave a historic concert to a crowd of 75,000 people. Her performance was a powerful moment of protest against racial discrimination and a celebration of African American artistry and achievement.