Concept:A monogastric animal has a simple, single-chambered stomach (like humans and pigs). A ruminant has a four-chambered stomach (rumen, reticulum, omasum, abomasum) and chews the cud.
Solution:Cattle: ruminant, four-chambered stomach.
Goat: ruminant, four-chambered stomach.
Sheep: ruminant, four-chambered stomach.
Rabbit: one simple stomach; it digests plant fibre in its large caecum instead of a rumen.
So the rabbit is the monogastric animal.
Answer:Option D (rabbit)