Describe the weather system approaching Vancouver Island.

The weather system approaching Vancouver Island is characterized by low pressure, which typically indicates unsettled weather conditions. Low pressure systems are often associated with stormy weather, clouds, precipitation, and strong winds. In this case, the measurement of 1001 mb indicates that the system is relatively strong but not at the extreme ends of the low-pressure scale, where hurricane-like conditions would occur.

The presence of gale-force winds is significant, as these winds can lead to rough sea conditions, which are critical considerations for sailing. Gale-force winds typically range from 34 to 40 knots, exerting considerable influence on both marine navigation and local weather patterns.

Other choices include high-pressure systems, which generally result in calm weather, clear skies, and gentle winds, making them less relevant to the question regarding an approaching weather system that is likely to bring more tumultuous conditions. The mention of developing gale winds in the other choices, while indicative of increasing wind strength, does not align with the low-pressure characteristics that characterize the system in question. Thus, the assessment that a low-pressure system with gale-force winds is approaching Vancouver Island is consistent with typical meteorological patterns associated with such systems.