The question is asking for the term that refers to a section in a train. 'Compartment' (A) is the correct answer as it is a small, enclosed space for passengers in a train. 'Carriage' (B) is another word for a train car but does not refer to a section within it. 'Classroom' (C) and 'Station' (D) are not related to sections within a train. Therefore, the correct answer is A.