Generate a question which can yield the answer mentioned in the input. Generated question must be answered by the answer provided in input, without using any extra knowledge.

Context : The LD&ECR Class D was a class of nine 0-6-4T steam locomotives supplied to the Lancashire, Derbyshire and East Coast Railway in 1904 and 1906 by Kitson & Co. of Leeds.
Answer : 1904
What was the year LD&ECR Class D entered service?