Is this mutton is red meat?

Mutton is the meat from adult sheep. Sheep meat is considered red meat.

Red meat is a term for mammalian muscle meat that has more myoglobin than white meat. Myoglobin is a protein that helps muscles store oxygen. Red meat is typically darker in color than white meat, and it has a richer, more intense flavor. Other examples of red meat include beef, pork, and lamb.