Zack is four years old and can do cartwheels, back flips, back hand springs, and one-handed cart wheels. he has had no formal training to develop these gymnast skills. all represent:

The correct answer is gross motor skills.

Gross motor skills are physical skills which require the movement of the entire body and the involvement of a wide range of the core muscles. These skills are used to perform everyday actions such as walking, running or kicking for example.

Gross motor skills are different from fine motor skills which involve smaller actions such as tasting things or picking up small objects.