Which type of muscle is known for being smooth and nonstriated?

The term "nonstriated muscle" describes smooth muscle, which is characterized by its lack of visible striations when observed under a microscope. This type of muscle is involuntary and is found in various organs throughout the body, including the digestive tract, blood vessels, and respiratory system. Smooth muscle cells are spindle-shaped and function to facilitate various involuntary movements, such as peristalsis in the intestines or vasodilation in blood vessels.

Understanding the structure and function of smooth muscle is crucial for appreciating how it operates differently from skeletal muscle, which is striated and under voluntary control, and cardiac muscle, which is striated but involuntary. While "connective muscle" is not a recognized category of muscle tissue, the emphasis on nonstriated characteristics directly points to smooth muscle, making it the correct answer.