What does the acronym TVMDC stand for?

The acronym TVMDC stands for True Course Variation Magnetic Deviation Compass. In navigation, this term is crucial for understanding how to reconcile readings from a magnetic compass with the true course of a vessel.

“True course” refers to the actual direction over the ground that a vessel is intended to travel, while “variation” denotes the difference between true north and magnetic north due to the Earth's magnetic field. “Magnetic deviation” addresses the errors introduced in compass readings by local magnetic fields. Understanding this acronym is important for navigators because it encompasses key concepts necessary for accurate navigation and helps ensure the safe operation of vessels. Therefore, option B correctly encapsulates these essential navigational terms and their relationships.