How far must you stop from a railroad track if there is no sign indicating a stop?

Answer: B — 15 feet from the track

Stopping 15 feet from the nearest railroad track when there is no sign indicating a stop is in accordance with the safety regulations set forth for drivers around railroad crossings. This distance allows for adequate visibility of any approaching trains while also ensuring that vehicles are not positioned too close to the tracks, which could expose them to danger. It also provides sufficient space for the vehicle to stop safely without risking collision. While options such as 5 feet, 25 feet, and 50 feet are distances that could be associated with various other road safety measures, they do not match the specific requirement for stopping at railroad tracks under normal circumstances without signage. Stopping too close can limit visibility and reaction time, while stopping excessively far away could lead to confusion about the crossing and create potential safety hazards or delays in traffic. Hence, stopping precisely at 15 feet strikes a balance between safety and practicality at unmarked railroad crossings.