The farm animal that is considered monogastric is the pig.
Monogastric refers to animals that have a single-chambered stomach that functions as a simple, acidic storage and digestion chamber. In other words, monogastric animals have a stomach that is not divided into multiple compartments.
Pigs have a monogastric digestive system, meaning that they have a single-chambered stomach just like humans. They digest their food through a process that involves the breakdown of food in the stomach and small intestine with the help of enzymes and acid.
In contrast, ruminant animals such as cows and sheep have a four-chambered stomach that allows them to digest tough plant material more efficiently. They use a process called rumination, which involves regurgitating and re-chewing their food to break it down further.
Therefore, the pig is the only animal in the given options that has a monogastric digestive system, while the others have multi-chambered digestive systems.