Definition: In this task, you're given a question, along with a context passage. The passage will not have a direct answer to the question, but can include some information and a clue for the answer. Assuming you can only obtain information about one entity in the passage, your job is to determine whether information from the passage can be used to answer the question. Indicate your choice as `a` for Yes or `b` for No.
Input: Question: How many soldiers served in the 67th Brigade? Passage:In early September 1914, 18-year old Lewis attended a recruitment meeting organised by a Major Birt, who was also his father's employer, which drew crowds of 2000–3000 people before enlisting in the 11th (Service) Battalion of the Welsh Regiment which had been formed little over a month before as the Cardiff Commercial Battalion, a pals unit. At 10 a.m. the next day, Lewis, was one of 75 local volunteers who left Milford Haven before being split into smaller groups with Lewis and 45 others travelling to Maindy Barracks in Cardiff, the rest joining the Royal Engineers or the Royal Artillery. Two days later, his unit was moved to Lewes as part of the 67th Brigade. He also underwent training at Eastbourne, Hastings, Aldershot and Seaford. On 5 September 1915, just over a year after enlisting, Lewis and his unit sailed to Boulogne, France from Southampton. Several days after his arrival, he was attached to the 9th Border Regiment as a machine gunner.


a