Final answer:
Involuntary control of smooth and cardiac muscles and glands is provided by the autonomic nervous system. It operates without the need for conscious thought and regulates essential bodily functions, including those that change during exercise such as increased heart rate. (Option A).
Step-by-step explanation:
The autonomic nervous system is responsible for the involuntary control of smooth and cardiac muscles and glands.
The system is a division of the peripheral nervous system that controls involuntary activities, such as digestion, heart rate, and sweating, without conscious effort from us.
This system is also responsible for managing the physiological changes that occur during exercise, like an increased heart rate and the production of sweat, as part of its regulation of the body’s internal environment.
The ANS is subdivided into the sympathetic and parasympathetic nervous systems, which have opposing effects on the body.
The sympathetic nervous system generally stimulates the body, preparing it for 'fight-or-flight' situations, whereas the parasympathetic nervous system promotes restful and digestive functions.
During exercise, the sympathetic division is more active, leading to the observed physiological changes.
Hence, the correct answer is the autonomic nervous system (Option A).