Answer:
A: her helmet aside
Explanation:
If we add the ending 'her helmet aside' to the sentence 'The skier moved', we complement the sentence and make the verb moved transitive. "The skier moved her helmet aside." This transitive verb needs a direct object: 'her helmet'. The endings in options B, C and D only make the verb 'moved' intransitive (verb that don't need an object.)
