A vein possesses a large lumen because

[A] Tunica Media And Tunica Externa Form A Single Coat

[B] Tunica Interna And Tunica Media Form A Single Coat

[C] Tunica Interna, Tunica Nicuiu And Tunica Externa Are Thin

[D] Tunica Media Is A Thin Coat

Answer & Explanation
Answer: Tunica Media Is A Thin Coat