Definition: In this task, you're given a question, a context passage, and four options which are terms from the passage. After reading a passage, you will get a brief understanding of the terms. Your job is to determine by searching and reading further information of which term you can answer the question. Indicate your choice as 'a', 'b', 'c', or 'd'. If you think more than one option is plausible, choose the more probable option to help you answer the question.
Input: Question: How long after the Second Blakan War did World War I begin? Passage:Ivan Mihailov was born on 26 August 1896, in the village of Novo Selo (now part of Štip Municipality, North Macedonia) in the Kosovo Vilayet of the Ottoman Empire. Mihailov studied at the Bulgarian Men's High School in Thessaloniki up until the Second Balkan War when the school was closed by the new Greek administration, he later continued his studies at a Serbian school in Skopje. He was offered a scholarship by the Serbian Ministry of Education to pursue a degree at a European university but declined, later enlisting in the Bulgarian army, which had by that time occupied a significant portion of the region. After the end of World War I, Mihailov emigrated to Bulgaria, settling in Sofia. Here he began studying law at the Sofia University, at which time he was contacted by IMRO activists and offered to work as a personal secretary for IMRO's leader at that time, Todor Aleksandrov.
 Links: a. Second Balkan War b. Todor Aleksandrov c. Second Balkan War d. Todor Aleksandrov
Output:
a