Which of these characters differentiates animals from all other groups of organisms?

Question

Quizplus · Accepted Answer

Gastrulation is the process by which the inner cell mass of a developing embryo goes through a series of cellular movements that result in the formation of three germ layers, which give rise to all the tissues and organs of the animal. This process is unique to animals and is the key developmental event that distinguishes them from all other groups of organisms. While multicellularity, heterotrophy, and mitochondria are important characteristics of animals, they are also found in other groups of organisms such as plants and fungi.

Which of These Characters Differentiates Animals from All Other Groups