Herbivorous means who eats plants and stems (etc) of plants only. cow eat only plants and stems(etc) of plants right. so cow is a herbivorous animal. then tiger,tiger eats only flesh of other animals they don't eat plants. so they are called carnivorous animals. then crow they eat both flesh and plants. so they are called omnivorous. then dog they also eat both flesh and plants. so they are also a omnivorous animal. so,last and finally there is only one animal that is herbivorous. that animal is cow right. so the answer is cow. thats all.