The answer would be D. People in Northern and Western Europe started planting and eating potatoes as an important source of nutrition.
Soviet union existed until 1991. russia is a part of the soviet union and was formed after the fall of the soviet union in 1991
North Africa is a region that is occupied by nations that are in the category of developing nations. Their economies are relatively weak, dependent on a single or handful of products or services, which makes them very vulnerable. The incomes of the people are pretty low, though there has been some slight improvement. The life expectancy is much lower than in the more developed nations, while being bigger than the sub-Saharan nations. A big problem is the literacy rate, as lot of people are still illiterate, especially the women, which limits the capabilities of the people and their economic input. The birth rates are very high, as in most of the nations of this type, but that causes more problems, as there is more and more population, while the development is very slow and can not keep up that pace.
Multiple factors were involved in the decision of exploration of Mars.
Mars is similar to Earth in size and it is the next planet. Moreover, evidence was present to suggest that liquid water existed, and may possibly still exist, on Mars. All of these factors led to the planet's exploration.
They weren't making money and no one was using it
