Final answer:
Helen's commercial property policy most likely included the Special Form coverage, which provides blanket coverage for all perils unless specifically excluded, hence covering the damage from snow and ice.
Step-by-step explanation:
Helen's commercial property policy covered the damage from the weight of ice and snow, despite it not being specifically listed. This scenario is indicative of the Special Form coverage in commercial property insurance. The Special Form is the most inclusive of the forms, offering a blanket coverage that includes all perils unless they are specifically excluded. This contrasts with the Basic and Broad Form, which only cover named perils. The absence of a Universal Form indicates that the correct answer is the Special Form (Option C).