Question

the ____ runs north and south and marks 0 degrees east and west. zero longitude prime meridian equator first meridian

Explanation:

The prime meridian is the line of 0 - degree longitude that runs north - south and serves as the starting point for measuring east - west longitudes. The term "zero longitude" is not the common name for this line. The equator runs east - west and marks 0 degrees latitude. There is no "first meridian" in standard geographical terms.

Answer:

B. prime meridian