Explanation:

Russia
- Russia has the highest geographical area among the given options.
- It is the largest country in the world in terms of land area, covering approximately 17.1 million square kilometers.
- Russia spans across two continents, Europe and Asia, and has a diverse landscape including forests, mountains, and tundra.
- The country has a vast expanse of territory, making it the largest country by land area.
- Due to its sheer size, Russia is home to a wide variety of ecosystems and biodiversity.

Comparison with other options:
- Canada is the second-largest country in the world by land area, followed by the United States and China.
- While Canada has a significant landmass, it is slightly smaller than Russia.
- The United States and China also have large geographical areas, but they are smaller in comparison to Russia.

Conclusion:
- In conclusion, Russia has the highest geographical area among the given options, making it the largest country in the world in terms of land area.

Geographical Area of Countries
The geographical area of a country refers to its total land area, including both land and water bodies. Among the given options, Russia has the highest geographical area. Here is a detailed explanation:
1. Canada:
- Canada is the second-largest country in the world by land area.
- It spans over 9.98 million square kilometers.
- It is known for its vast forests, mountains, and numerous lakes.
2. Russia:
- Russia is the largest country in the world by land area.
- It covers about 17.1 million square kilometers.
- It extends across two continents, Europe and Asia.
- It has diverse landscapes, including tundra, taiga, and steppe regions.
3. USA:
- The United States is the third-largest country by land area.
- It has a total land area of approximately 9.83 million square kilometers.
- It is located in North America and consists of 50 states.
- The country has a diverse range of geography, including plains, mountains, and coastal areas.
4. China:
- China is the fourth-largest country by land area.
- It spans over 9.59 million square kilometers.
- It is located in East Asia and shares borders with several countries.
- China has various geographical features, such as deserts, mountains, and plateaus.
Conclusion:
Among the given options, Russia has the highest geographical area. It covers approximately 17.1 million square kilometers, making it the largest country in the world.