Which of the following describes the function of smooth muscle?

The function of smooth muscle is accurately described by its role in controlling the movement of internal organs. Smooth muscle is found in the walls of hollow organs such as the intestines, blood vessels, bladder, and stomach. Its primary function is to facilitate involuntary movements, which are essential for processes like digestion, blood circulation, and elimination of waste without conscious control.

Smooth muscle contractions are generally slow and sustained, allowing for the effective movement of substances through these organs. For example, peristalsis, the wave-like contractions in the intestines, helps in the movement of food along the digestive tract.

In contrast, the other options focus on functions that are primarily associated with different types of muscle. Voluntary movements are typically managed by skeletal muscle, which allows for conscious control of movement. Rapid reflex responses are more closely related to skeletal muscle functioning in conjunction with the nervous system. Lastly, while skeletal muscle is responsible for enabling motion against gravity and performing tasks that require strength and coordination, it does not pertain to the involuntary processes managed by smooth muscle.