How are M-3 cars designated?

The designation of M-3 cars utilizes a systematic numbering convention where even-numbered cars are classified as “A” cars and odd-numbered cars as “B” cars. This means that if you look at a series of M-3 cars, you will find that every even-numbered unit corresponds to the “A” category, while every odd-numbered unit corresponds to the “B” category. This organization helps in maintaining uniformity and eases the process of identifying and distinguishing between the two types of cars in service.

This numbering system is important for operational and logistical reasons, providing clear guidelines for train crews and maintenance personnel. It ensures that both types of cars can be easily referenced and managed as part of the fleet operations. By employing a simple numerical system, it reduces confusion and enhances communication among staff.

In contrast, the other options suggest alternate systems for classification that do not align with the established protocol for M-3 cars. Adopting any other method would complicate identification and could lead to potential operational inefficiencies or errors.