Final answer:
In the provided sentence, 'cookies and cupcakes' form a compound direct object, meaning they are both receiving the action of the verb 'prepared'.
Step-by-step explanation:
In the given sentence, 'The pastry chef prepared cookies and cupcakes for the younger guests, 'cookies' and 'cupcakes' seem to be underlined. These words are functioning as the objects of the sentence and there are two of them, linked by the coordinating conjunction 'and'. Therefore, they form a compound direct object. Both 'cookies' and 'cupcakes' are receiving the action of the verb 'prepared' which is performed by the subject, 'the pastry chef'.
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