The latitude of a place expresses its angular position relative to the plane of

axis of earth
north pole
south pole
equator

The correct answer is: D. equator.

Latitude is a geographic coordinate that specifies the north–south position of a point on the Earth’s surface. It is an angular measurement expressed in degrees, minutes, and seconds, north or south of the Earth’s equator. The equator is the line of zero degrees latitude. It divides the Earth into the Northern and Southern Hemispheres.

The other options are incorrect because they are not lines of latitude. The Earth’s axis is an imaginary line that runs through the North and South Poles. The North Pole is the northernmost point on Earth, and the South Pole is the southernmost point on Earth.