It is definitely not true that many small rural communities have best transport, so we can reject the option b) and d) together with it.
The best answer is that they don't have mass transit systems (a is the correct answer). It's not true that they can walk everywhere because they can for example be forced to walk to a different town if they need a hospital.
Pretty sure it's about the branches of the government.
Geography has a profound effect on where civilizations settle. The earliest civilizations resided within river valleys, and used the area around them to create opportunities to benefit their growth. Mountains, rivers, and plateaus provided natural defenses, at the cost of movement and trade.
