Final answer:
The precise speed limit on non-posted rural roads cannot be determined without local legal context, though it's important to know your speed limit and to consider that 50 km/h is typical for residential areas, equating to roughly 31 miles per hour.
Step-by-step explanation:
The speed limit on non-posted rural roads varies depending on the jurisdiction, but since the information provided references speed limits in kilometers per hour (km/h) and the fact that 50 km/h is typical for residential areas, it's important to consider this as a starting point. However, without specific local jurisdictional information, a default rule for non-posted rural roads is not provided here. Instead, one should default to respecting the general rural road speed limits established by the local or national authority governing the area in which they're driving.
For instance, if we assume 50 km/h in residential areas is a given, and it equates to approximately 31 miles per hour, one could argue that on non-posted rural roads in some places, the speed limit might be slightly higher to account for less traffic and pedestrian activity. However, a specific option from the provided choices (a. 25 mph, b. 35 mph, c. 45 mph, d. 50 mph) cannot be confirmed as correct without proper local legal context.
This information underlines the importance of knowing your speed limit and road safety on rural roads. Always look for posted speed limit signs or consult local traffic laws to determine the correct speed.