Question 651Navigation General

The correct answer is B) cannot correct. Variation is a compass error caused by the magnetic influence of the Earth's magnetic field on the compass. It cannot be corrected by the mariner, as it is influenced by the vessel's geographic location and the Earth's magnetic field, which are outside the mariner's control. The other options are incorrect because adjusting the compass card, compensating magnets, or changing the vessel's heading will not correct the variation error, which must be accounted for by referencing published variation charts or tables.