The correct answer is option 'A' - Great Basin.

The Great Basin is an inland drainage system characterized by small, seasonal rivers that terminate in saline lakes. This unique hydrological feature is primarily found in the western United States, specifically in the region between the Sierra Nevada and Rocky Mountains.

Here is a detailed explanation of why the Great Basin is the correct answer:

1. Definition of the Great Basin:
- The Great Basin refers to a vast region of interior drainage in the western United States.
- It covers portions of Nevada, Utah, Oregon, California, Idaho, and Wyoming.

2. Small, Seasonal Rivers:
- The rivers in the Great Basin are generally small in size and have limited flow.
- They are often referred to as ephemeral or intermittent rivers because they only carry water during certain periods of the year, primarily during the spring and early summer.
- These rivers are fed by snowmelt from the surrounding mountains and experience high flow during this period.

3. Termination in Saline Lakes:
- One of the defining features of the Great Basin is the presence of numerous saline lakes.
- These lakes are the ultimate destination for the small rivers that flow within the region.
- Due to the arid climate and lack of outlets for the rivers, the water accumulates in these closed basins and evaporates over time, leaving behind high concentrations of salts and minerals.
- Examples of saline lakes in the Great Basin include the Great Salt Lake in Utah, Pyramid Lake in Nevada, and Mono Lake in California.

4. Importance and Challenges:
- The Great Basin's unique hydrology and saline lakes have significant ecological and economic importance.
- The region supports a variety of specialized plant and animal species that have adapted to the harsh conditions of the arid landscape.
- The saline lakes also provide habitat for migratory birds and support commercial activities such as salt extraction and recreational activities like boating and fishing.
- However, the Great Basin faces several challenges, including water scarcity, habitat degradation, and the introduction of non-native species.

In conclusion, the Great Basin is an inland drainage system characterized by small, seasonal rivers that terminate in saline lakes. This unique hydrological feature is found in the western United States and has both ecological and economic significance.