The correct answer is: D. None of the above
The jet stream is a fast-flowing, narrow air current found in the upper atmosphere. It flows from west to east in the Northern and Southern Hemispheres. The jet stream is strongest in the winter and weakest in the summer.
The jet stream is not a straight line. It has waves, which are called Rossby waves. The ridges of the waves are where the jet stream is closest to the Earth’s surface. The troughs of the waves are where the jet stream is farthest from the Earth’s surface.
The jet stream is important because it affects the weather. The location of the jet stream affects the temperature and precipitation patterns in different parts of the world.
The poles are the points on the Earth’s surface that are farthest from the equator. The equator is the line that divides the Earth into the Northern and Southern Hemispheres. The prime meridian is the line that runs through Greenwich, England.
The jet stream does not close to any of these points. It is a continuous band of air that flows around the Earth.