Final Answer:
When making up trains in a yard in very cold weather, the train operator could expect to find trouble with the brakes. Option A is answer.
Step-by-step explanation:
In extremely cold weather, train operators may encounter challenges related to the braking system. Cold temperatures can affect the functionality of air brakes, a common braking system in trains. The air brake system relies on compressed air, and extreme cold can cause issues such as frozen moisture in the brake lines, which may hinder the proper operation of the brakes.
Cold weather can also impact other components, but brakes are particularly susceptible to temperature-related challenges. Regular inspections and maintenance become crucial in such conditions to ensure that the braking system operates effectively. Train operators need to be vigilant and address any issues promptly to maintain the safety and functionality of the trains during cold weather operations.
Option A is answer.