Which fuse designation corresponds to the description: Normal switch position route selection relay, southward initiation "A" end of crossover?

• A. Normal switch position route selection relay, northward initiation, "A" end of crossover.
• B. Normal switch position route selection relay, southward initiation "A" end of crossover.
• C. Low air pressure alarm push button.
• D. Approach locking stick relay.

Answer: (B)

Fuse designations in signaling identify exactly what equipment, where it initiates, and from which end or direction it operates. The description here specifies a normal switch position route selection relay that initiates from the south toward the A end of the crossover. The designation that uses those exact terms—and puts the initiation as southward from the A end of the crossover—fits this scenario precisely. That alignment with the described function and direction makes it the best match. The other options point to different initiation directions or to different types of devices, so they don’t describe the same setup.