Which Statement Accurately Describes the Most Important Difference Between Cardiac

Which statement accurately describes the most important difference between cardiac muscle and smooth muscle?

A) Smooth muscle is under voluntary control, whereas cardiac muscle is not.
B) Cardiac muscle has special junctions called intercalated discs that smooth muscle does not.
C) Smooth muscle has no role in controlling blood pressure, whereas cardiac muscle does.
D) Cardiac muscle is found in blood vessels, whereas smooth muscle is found in other organ systems, such as the respiratory and digestive tracts.