The Number of Degrees of Longitude That a Place Has

The number of degrees of longitude that a place has is derived from the angle formed by the place's location on the Earth surface,

A) the center of the Earth at the same latitude,and the North Pole (if in the Northern Hemisphere) or South Pole (if in the Southern Hemisphere) .
B) the center of the Earth,and the equator.
C) the center of the Earth at the same latitude,and the Prime Meridian at the same latitude.
D) the center of the Earth at the same latitude,and the International Date Line at the same latitude.