The correct answer is C) small circle. A parallel of latitude other than the equator is a small circle on the Earth's surface. A small circle is defined as a circle on the surface of a sphere where the plane of the circle does not pass through the center of the sphere. In contrast, a great circle is a circle on the surface of a sphere where the plane of the circle does pass through the center of the sphere, such as the equator. The other options are incorrect: A) great circle is not correct because parallels of latitude are not great circles, B) gnomonic curve is a type of map projection, not a geometric shape on the Earth's surface, and D) loxodromic curve is a curve that intersects all meridians at the same angle, which is not the same as a parallel of latitude.