Question

why did the development of time zones make train schedules more reliable?
time zones set the entire country to the same time.
time zones measured time locally instead of country - wide.
time zones made sure that each state was in only one zone.
time zones created a standard of time that all trains followed.

Explanation:

To determine the correct answer, we analyze each option:

• Option 1: Time zones don't set an entire country to the same time (they divide regions into zones), so this is incorrect.
• Option 2: Time zones are about standardizing time across regions, not just local measurement, so this is wrong.
• Option 3: The reliability of train schedules isn't about each state being in one zone, so this is incorrect.
• Option 4: Time zones created a standard time that all trains could follow, eliminating confusion from different local times, making schedules more reliable.

Answer:

D. Time zones created a standard of time that all trains followed.