Most of the nutrients that plants depend on to grow are found in very thin quantities in soil right by the surface. This fertile soil is called “topsoil,” and it is here where almost all crops are grown. To this author’s knowledge none of the other answer choices are real terms.

Bolivia is one of the poorest and least developed countries in South America. In the 1980s, it owed hundreds of millions of dollars to international and multinational banking organizations. In an unprecedented move the debt was forgiven in exchange for Bolivia’s guarantee that it would preserve more than a million square miles of its rainforest. This type of agreement made with Bolivia is called a “Debt-for-nature swap.”

Slash and burn is an agricultural technique used today in tropical forest regions with small populations and shifting cultivation agriculture. It uses little technology, and has been practiced since the Neolithic Revolution. Though the technique is not sustainable in large populations, because without the trees, the soil quality becomes too poor to support crops, the method is suitable for small farming communities. 

Deforestation refers to the clearing of forest or jungle to make room for agricultural or mining industries. It is a significant problem around the world, but is most pronounced in South America. The Amazon Rainforest in South America is being cleared at a rapid rate to make room for ranches, plantations, and mining industries. This presents a serious ecological problem for the entire continent.

The Department of Agriculture was created in 1862 by President Abraham Lincoln. At the time the vast majority of Americans were engaged in farming as their primary occupation and so Lincoln called the newly created department “The People’s Department.”

“Degraded agricultural land” is land that was once fertile and used for growing crops, but has been made infertile by human intervention and mismanagement. It is most common in densely populated areas where large scale farming has been common for a long period of time. For this reason, North America, which is not very densely populated and has only been consistently farmed since the arrival of Europeans, has the lowest percentage of degraded agricultural land.

“Topsoil erosion” refers to the gradual (or occasionally, rapid) depletion of the nutrient-rich topsoil in which almost all crops are grown. It is of such large concern because topsoil can take hundreds or thousands of years to replenish itself. Topsoil is found throughout the world and both the developed and developing world depend on crops grown in topsoil.

The Kyoto Protocol was signed in 1997 by more than 80 countries. This protocol's main goal was to reduce the emission of greenhouse gases (e.g., methane). The United States abandoned this protocol due to a fear of restricting growth.

Warmer sea surface temperatures, increases in sea level, and reduced biodiversity are all negative consequences of climate change. The ultimate cause of climate change is increased fossil fuel usage, which has negative implications for many aspects of life as we know it. 

The idea of environmental determinism states that the physical environment can direct human social development and culture towards certain patterns and trajectories. In other words, the physical environment can determine the fate of human culture to an extent.