Greenwich Mean Time, or GMT, is Earth's internationally agreed upon official time reference.

Mt. Everest is the tallest mountain on Earth. Its summit, more than 29,000 feet high, is located at the border of Nepal and China.

The "torrid zone" is another name for the tropics, which describes the areas between the Northern Hemisphere's Tropic of Cancer and the Southern Hemisphere's Tropic of Capricorn. These lines of latitude mark the points furthest from the Equator where the sun can still be directly overhead at any point during the year. The areas within the "torrid zone" are the warmest places on earth, featuring rainforests and other tropical environments.

The term “idiographic” is used to describe or refer to a feature that is unique to a particular geographic region. It is distinct from “nomothetic” which means a feature or theory that is universally applicable across a multitude of regions.

Climate change and global warming are environmental changes caused by human actions. The term used to describe this phenomenon is “anthropogenic.”

Possibilism is a cultural-geography theory that evolved from the racially informed theory of environmental determinism. Environmental determinism argues that environmental conditions provide constraints on the growth of culture in many parts of the world. On the other hand, possibilism concedes that environmental conditions provide a broad range of cultural limitations and advantages for various regions of the world; however, it contends that culture is otherwise determined by the environment's social conditions.

The concept of “placelessness” refers to the homogenizing effect of cultural diffusion, particularly in the modern world. It was developed by the cultural geographer Edward Relph in the 1970s. According to Relph, the spread of pop culture and globalization was leading to an inevitable breakdown of the individual identity of communities, causing one place to closely resemble another place, and, eventually all other places.

The term “nomothetic” means a feature that is universally applicable across a multitude of regions. It is distinct from “idiographic” which describes a particular feature that is unique to a certain geographic region. The idiographic is usually the concern of local or regional geographers who are concerned with a narrow, but deep, understanding of a relatively small geographic region. Whereas nomothetic is usually the concern of systematic geographers who are concerned with universal features and aspects of Earth’s geography.

Quantitative data, as distinct from qualitative data, relies on numbers and mathematical models. “Quantitative” means measures using numerical facts. Quantitative data has become more and more important in geographic inquiry because it leads to more objective, less personally motivated, conclusions.

A “perceptual region” is a region that exists only in the minds of people. It is not a formal boundary, nor is it perceived uniformly by each person. For example whilst we can all agree on the region that encompasses the United States we might not all agree on the region that encompasses the “fly over states.” "The Deep South" is a perceptual region of the United States with no defined boundary. What someone from one area of the country would call "the Deep South" may be hotly disputed by a person from another part of the country. The difference between the southern states (south of the Mason Dixon Line) and "the Deep South" is purely perceptual. All the other answer options have clearly delineated physical boundaries or features.