The violent act in Bosnia that triggered World War I was t<span>he assassination of Franz Ferdinand, the heir to the Austro-Hungarian throne and his wife in Sarajevo on June 28, 1914. The assassin was Gavrilo Princip, a member of a Serbian nationalist group, called </span>Black Hand<span>. The correct answer among the options given above is letter "B."</span>
They figured out that they could grow plants so they did that and they got food and that was their new way of getting food.