The parallel of latitude at 23°27'S is the __________.

Correct Answer: Option B — Tropic of Capricorn

The Tropic of Capricorn is defined as the parallel of latitude at 23°27' South, representing the southernmost point where the sun can appear directly overhead. This is a fundamental geographic constant used in celestial navigation and astronomy, as established in the Nautical Almanac and standard navigational reference texts.