Silk Roads/Land routes
Sea Lanes
Railroads on the Railways required tracks for the trains to run on them these tracks earlier made up of iron for its heavy duty but soon enough realise that iron was not a very good option for tracks. Meaning drawbacks of using iron for example rusting is it was realised that Steel was a better option in making railroads.
Steel being made out of iron is heavy duty material yet it is not much prone to rusting. Just addition of certain minerals and carbon in iron steel forging is done making it heavy duty material.
The correct answer is - B. Economies around the world have become more interconnected because of globalization.
In the modern era, the globalization took a massive swing worldwide, and most of the countries became much more connected with each other through the means of economy. The main players of the globalization process are the big corporations which set affiliations throughout the world, and managed to gain many new markets for their ever growing production of goods. Apart from the likes of North Korea, Iran, Turkmenistan, and countries similar to them, most of the world is already or is heading towards the globalization trend. It is a process that has its supporters and critics, depending on the point of view, and to a certain extent both sides have good arguments for their claims.
