What describes the tracks between the opposing home signals of an interlocking?

• A. Main Track
• B. Movement Permit Form D
• C. Interlocking Limits
• D. Movable Point Frog

Answer: (C)

Interlocking limits describe the portion of track that the interlocking protects, i.e., the tracks between the opposing home signals. This area is bounded by those signals and includes all routes within the interlocking that switches and signals control to prevent conflicting movements. The other options don’t fit: the main track is just a classification of track outside the interlocking, a movable point frog is a switch component, and a Movement Permit Form D is an administrative document, not a track description.