Though it stayed strictly indoors, the small dog felt like it had all the space in the world in the what?\nOptions:\n- living room\n- dog park\n- basket\n- small apartment\n- big house
Step-by-step reasoning process below:

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In big house, the small dogs stayed strictly indoors. The small dog felt like it had all the space in the world in the big house. The answer: big house.
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