Final answer:
The correct use of the Spanish preposition 'para' in the sentence 'Elena trabaja para su tío' is 'employed by'.
Step-by-step explanation:
The correct use of the Spanish preposition para in the sentence 'Elena trabaja para su tío' is 'employed by'. In this context, 'para' indicates the purpose or employment of someone. So, the sentence translates to 'Elena works for her uncle.'
Learn more about Spanish prepositions