Which statement best describes how time zones are oriented along longitude?

• A. Time zones are oriented by latitude bands rather than longitude.
• B. Every 15º is a Central Meridian, and the time zone extends 7.5º on either side.
• C. Time zones are centered on the Prime Meridian only.
• D. Each time zone covers 30º of longitude.

Answer: (B)

Time zones align with longitude because the Earth rotates 360° in 24 hours, so time changes by one hour for every 15° of longitude. In the standard scheme, each time zone has a central meridian at multiples of 15° (0°, 15°, 30°, etc.), and the zone extends about 7.5° on either side, making each zone 15° wide. While political boundaries can push boundaries away from this ideal, the basic orientation is along longitude centered on those 15° meridians. The other statements wobble from this concept by focusing on latitude, claiming only the Prime Meridian as a center, or asserting a 30° width.