What major event prompted 120,000 workers to go on strike in St. Petersburg in 1905?

The correct response identifies the significance of Bloody Sunday, which occurred on January 22, 1905, when peaceful demonstrators marching to present a petition to Tsar Nicholas II were shot at by soldiers, resulting in a massive outcry and unrest across Russia. This horrific event not only killed and injured many but also galvanized the labor movement and widespread dissatisfaction with the Tsar's regime. The shock of this brutal suppression of peaceful protest prompted a wave of strikes, including the significant strike involving 120,000 workers in St. Petersburg.

Bloody Sunday served as a catalyst for the 1905 Revolution, highlighting the deep social and political discontent among various classes, particularly workers and peasants, leading them to demand reforms and better working conditions. This moment marked a critical turning point in Russian history, as it signaled the beginning of organized protests against the autocracy and increased demands for political change.