Labrador Retriever
Outgoing with everyone, regardless of species, and with a low prey drive. A Lab is far more likely to try to carry a cat around gently than to go after it, and it is smart enough to learn and respect a cat's boundaries.
Energy is the honest drawback. An under-exercised Lab turns that friendliness into pestering, so this pick suits a household ready for long daily walks. A calm older Lab is one of the easiest dogs to bring into an established cat home.
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