What causes superstructure icing (ice accretion) on a vessel, and how does this hazard fundamentally differ from the sea ice/iceberg risk covered elsewhere in this content?

A. Ice accretion has no effect on a vessel's stability and is purely a cosmetic or minor operational inconvenience

B. Superstructure icing can only occur in air temperatures above freezing, making it irrelevant to genuinely cold polar operations

C. Superstructure icing only occurs when a vessel is in direct contact with pack ice or icebergs, making it functionally identical to the collision risks already covered

D. Superstructure icing is caused by freezing sea spray, freezing rain, or fog depositing water onto the vessel's exposed structure (deck, rigging, rails, superstructure) in sub-zero air temperatures, where it accumulates and freezes in place — unlike sea ice or icebergs, which threaten the hull from outside via collision or besetment, icing is a stability hazard that builds weight and raises the vessel's centre of gravity from above, with no need for the vessel to be anywhere near pack ice or icebergs at all

A. Vessel size has no bearing on the relative risk posed by a given amount of accreted ice

B. Ice accretion capsize risk depends solely on air temperature and has no relationship to vessel size or stability margin at all

C. A given mass of accreted ice represents a much larger percentage of a small vessel's total displacement and a proportionally greater rise in centre of gravity relative to its (generally smaller) margin of stability, compared to the same ice mass on a much larger vessel — small vessels with high topside structure (masts, rigging, gear) relative to their hull size are especially vulnerable

D. Larger vessels are always more vulnerable to ice accretion capsize risk than smaller vessels, reversing the actual relationship

A. Low air temperature (well below freezing) combined with strong wind generating significant sea spray, particularly when the vessel is heading into or across the weather such that spray is regularly thrown over the bow/sides onto exposed structure — the combination of cold air and wind-driven spray icing rate is far more severe than either factor alone

B. Air temperature has no bearing on icing rate; only wind speed determines how quickly ice accumulates

C. Icing is most severe in calm conditions with no wind or spray, regardless of air temperature

D. Icing only occurs when the vessel is stationary and never occurs while underway, regardless of conditions