The cart-wheel appearance of the tympanic membrane in ASOM is due to: (A) Perforation of tympanic membrane, (B) Edema of tympanic membrane, (C) Granulation tissue on tympanic membrane, (D) Congested blood vessels along malleus
Answer is D. In the stage of pre suppuration of ASOM, there is congestion of pars tensa. 
A leash of blood vessels appears along the handle of malleus and at the periphery of tympanic membrane imparting it a cart-wheel appearance.