Secondary host of Taenia solium is
Taenia solium, also known as pork tapeworm is an intestinal parasite found throughout the world and is most prevalent in countries where pork is eaten. Mode of transmission is consumption of undercooked pork or on ingesting faecally contaminated water or food. In Taenia solium, the primary or definitive host is human and then the larva is transmitted to pig through contaminated faeces. Hence, pigs are the secondary host of Taenia solium. So, the correct answer is 'Pig'.