At what altitude do jet streams typically operate?

Jet streams are high-altitude, fast-flowing air currents that occur at the boundary of different air masses in the atmosphere. They are typically found at altitudes ranging from about 30,000 to 35,000 feet, which aligns with the correct answer.

At this altitude, jet streams can significantly influence weather patterns by affecting the movement of air masses and storm systems. In aviation, understanding jet streams is crucial because they can affect flight times and fuel consumption. Pilots often take advantage of jet streams to reduce flight times when flying in the same direction as the stream, while they must also be cautious when flying against them as it can lead to increased flight duration and turbulence.

Other altitude ranges mentioned in the choices, while they may have different types of air currents, do not encompass the typical operational range of jet streams, which is primarily located in the upper troposphere. This high-altitude positioning is why option C is the most accurate representation of where jet streams commonly exist.