A signal at interlockings in ABS territory governing the use of an interlocking and the block beyond, protected by TSS?

• A. Automatic Block Signal
• B. Signal Interlocking ABS
• C. General Notice
• D. Single Track Operation

Answer: (B)

The key idea is identifying the signaling designation for a signal that sits at an interlocking within an Automatic Block Signaling (ABS) system and controls both the interlocking and the block beyond, with protection provided by TSS. In this context, the term that fits best is Signal Interlocking ABS. It explicitly describes an interlocking signal operating in ABS territory, where the interlocking logic and the adjacent block are safeguarded by ABS and the Train Safety System (TSS).

An Automatic Block Signal would refer to the general block signaling system itself, not specifically to a signal at an interlocking. A General Notice is an administrative instruction, not a signaling designation. Single Track Operation describes a track configuration, not the type of signaling at an interlocking.