Answer:
The dog is grateful to its owner.
In this sentence, the appropriate preposition to use is "to." We use the preposition "to" when expressing gratitude towards someone.
Here's an example to help illustrate the usage of "to" in this context:
Example: "The dog is grateful to its owner for taking care of it and providing love and support."
Using the preposition "to" shows that the dog feels thankful towards its owner for their actions and the care they have given.
Step-by-step explanation:
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