Final answer:
The line on the opposite side of Earth from the Prime Meridian, where East meets West, is called the International Date Line, and it denotes the point where one day changes to the next. It is not a straight line and is adjusted to accommodate political and geographic needs.
Step-by-step explanation:
The −180 meridian is found on the opposite side of Earth from the prime meridian and marks the location where East meets West. The correct name for this line of longitude is the International Date Line (B). It's essentially an imaginary line that is used to denote the change of one calendar day to the next. The actual International Date Line deviates from the 180-degree meridian in several places to accommodate political boundaries and geographic necessities.
The Prime Meridian (0 degrees longitude), located at the Royal Observatory in Greenwich, England, is the reference line from which all other lines of longitude are determined. Conversely, the International Date Line is roughly based on the 180-degree meridian, situated directly opposite the Prime Meridian. It's important not to confuse the Prime Meridian with the International Date Line since their functions are quite distinct, with the former being the zero reference point for longitude measurements while the latter serves to mark the transition between calendar days.
As each day begins at 12:01 a.m. at the International Date Line, it follows that this line plays a crucial role in timekeeping, although it is configured to prevent the division of sovereign territories or significant social regions. The line bends and curves to ensure that nations and islands maintain the same date within their borders, causing the actual path of the International Date Line to stray from the 180-degree longitude in several instances.