Final answer:
The correct answer is D. 'les'. In this sentence, the parents are asking their children to do many chores, and the pronoun 'les' is used to indicate the plural form of the children.
Step-by-step explanation:
The correct answer is D. les. In this sentence, 'Los padres siempre les piden a sus niños mucha tarea', the verb 'piden' (ask) is referring to the parents asking their children to do many chores. The pronoun 'les' is used to indicate that the parents are asking the children (plural), so it is the appropriate choice in this context.
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