Which is the correct explanation for 30°S latitude?   A. All positions along a circle that runs parallel to the equator and 30° north of it.   B. All positions along a circle that runs parallel to the equator and 30° south of it.   C. All positions along a circle that runs perpendicular to the equator and 30° south of it.   D. All positions along a circle that runs perpendicular to the equator and 30° north of it.