Question

horizontal lines that measure north or south is called _ and the center (0 degrees) is called _.
a longitude, equator
b latitude, equator
c longitude, prime meridian
d latitude, prime meridian

Explanation:

Horizontal lines measuring north/south are latitude. The 0-degree latitude line is the Equator. Longitude refers to vertical east-west lines, with the Prime Meridian as 0-degree longitude.

Answer:

B. Latitude, Equator