Small circle is defined as which of the following?

• A. The Intersection of a Plane That Passes Through the Center of the Sphere With the Surface
• B. The Line of Longitude That Passes Through the Poles
• C. The Intersection of a Plane That Does Not Pass Through the Center of the Sphere With the Surface
• D. A Great Circle

Answer: (C)

A small circle appears when a plane slices a sphere but does not pass through the center. The intersection forms a circle smaller than the sphere’s largest circle. If the plane did pass through the center, the intersection would be a great circle—the largest possible circle on the sphere. A line of longitude (meridian) is tied to a plane that goes through the center, so it represents a great circle when extended around the globe. Lines of latitude other than the equator come from planes parallel to the equatorial plane and do not pass through the center, making them small circles. Therefore, the description that matches a small circle is the intersection of a plane that does not pass through the center with the surface.