The correct answer is C. C & W.
C & W stands for Car and Wagon. The Car and Wagon department is responsible for the maintenance and repair of railway cars and wagons. They are also responsible for the marshaling of trains, which is the process of assembling a train and preparing it for departure.
The first officer of the C & W department to arrive or present shall be responsible for the marshaling of the BD Special. This is because they are the most familiar with the train and its equipment. They are also responsible for ensuring that the train is safe to depart.
The other options are incorrect. Engineering is responsible for the maintenance and repair of railway infrastructure, such as tracks and bridges. Mechanical is responsible for the maintenance and repair of railway locomotives and other rolling stock. None of these departments are responsible for the marshaling of trains.