In this task, you're given a question, along with a context passage which has extra information available on certain terms mentioned in it, i.e., the proper nouns in the passage. Your job is to determine whether information from more than one term is needed to answer the question. Indicate your choice as 'a' for Yes or 'b' for No.

Question: How many years after the conclusion of World War I was Boris made a major general? Passage:He received his initial education in the so-called Palace Secondary School, which Ferdinand had created in 1908 solely for his sons. Later, Boris graduated from the Military School in Sofia, then took part in the Balkan Wars. During the First World War, he served as liaison officer of the General Staff of the Bulgarian Army on the Macedonian front. In 1916, he was promoted to colonel and attached again as liaison officer to Army Group Mackensen and the Bulgarian Third Army for the operations against Romania. Boris worked hard to smooth the sometimes difficult relations between Field Marshal Mackensen and Lieutenant General Stefan Toshev, the commander of the Third Army. Through his courage and personal example, he earned the respect of the troops and the senior Bulgarian and German commanders, even that of the Generalquartiermeister of the German Army, Erich Ludendorff, who preferred dealing personally with Boris and described him as excellently trained, a thoroughly soldierly person and mature beyond his years. In 1918, Boris was made a major general.
b