A compass is usually held “horizontally” (so that the needle lies in a horizontal plane)...

A compass is usually held “horizontally” (so that the needle lies in a horizontal plane). However, the Earth’s magnetic field has both horizontal and vertical components (Fig. 20.42). Your friend is an arctic explorer and pitches his tent directly over the Earth’s south magnetic pole. Will his compass needle point (a) toward the Earth’s north geographic pole, (b) downward, or (c) upward?

(reference figure 20.42)