Definition: 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.
Input: Question: Which submarine did Ian McIntosh command for the longest amount of years? Passage:He served aboard the submarines HMS Porpoise and HMS Thrasher earning the Distinguished Service Cross for his service in the latter in 1942. As commanding officer of the submarine HMS Sceptre he sank almost 15,000 tons of enemy shipping and took part in Operation Source, the attacks on heavy German warships in Norwegian waters by towed midget submarines. He commanded the submarine HMS Alderney from 1946, the submarine HMS Aeneas from 1950 and then the aircraft carrier in the 1960s. He became Director-General Weapons (Naval) at the Ministry of Defence in 1969 and Deputy Chief of the Defence Staff (Operational Requirements) in 1970 before retiring in 1973.


a