Choose the correct description of a typical medium-sized vein.
A) In these vessels, the thin tunica media is surrounded by a thick tunica externa composed of mostly collagen fibers.
B) Ranging from 2 mm to 9 mm in diameter, its thin tunica media consists of one to two layers of smooth muscle cells.
C) It has a diameter of approximately 0.4 cm and has more smooth muscle cells and fewer elastic fibers.
D) It ranges from 2 mm to 9 mm in diameter, and the relatively thick tunica externa has longitudinal bundles of elastic and collagen fibers.
E) It has a diameter up to 2.5 cm, and its tunica media is dominated by elastic fibers rather than smooth muscle cells.
D) It ranges from 2 mm to 9 mm in diameter, and the relatively thick tunica externa has longitudinal bundles of elastic and collagen fibers.
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