Mark the statement that is incorrect for smooth muscles

Options

A. Smooth muscles form the muscular component of the visceral organs such as blood vessels, urinary bladder, ciliary body etc.
B. Smooth muscles cells do not have the troponin tropomyosin mechanism of controlling contraction
C. Irritability is shown by all smooth muscles except ciliary muscles
D. Hair root muscles and muscles on the large blood vessels are an example of multi-unit smooth muscles