Concept:Knowing the correct chronological periods of the First and Second World Wars.Explanation:The First World War took place from 1914 to 1918. The Second World War took place from 1939 to 1945. The word "respectively" matches the order given in the question. Thus, the correct sequence is 1914-1918 for the First World War and 1939-1945 for the Second.Answer:B. 1914-1918, 1939-1945