Final answer:
The correct direct object pronoun to complete the sentence is 'le' and the correct response would be 'Oui, il l'adore!'
Step-by-step explanation:
The correct direct object pronoun to complete the sentence is le.
So the correct response would be Oui, il l'adore!
The pronoun le is used here because 'chien' is a masculine singular noun, so we use the masculine singular pronoun le.
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