The correct answer to this open question is the following.
Although there are no options attached we can answer the question.
Unfortunately, you forgot to mention what was the lesson from class or what was your textbook. We cannot provide examples from those sources because you do not attach any references. We do not know what they are.
You neither mention the time in history, the place, or the civilization you are referring to.
However, what we can do in order to help you is to answer based on our knowledge of the topic.
You are probably referring to ancient civilizations such as the Incas in South America.
A major effect of having a well-organized society, a system, of roads, and a powerful army was that these civilizations such as the Incas of Machu Pichu, Perú, in South America, were able to build a great and powerful empire, conquest other tribes, establish a solid trade system using those good roads they constructed, develop sophisticated agriculture techniques for their time, live in prosperity and continuous growth.
The Incas were a well-organized society, built a system of roads, and a powerful army that allowed the Emperor to extend his control and power to other far tribes that paid tribute. The Incas built impressive roads that facilitated the transportation of people and goods to different parts of the Andes mountains.