All of the following are reasons why acute otitis media (AOM) is more prevalent in children under the age of four except: adenoids can block the opening of the Eustachian tube in young children.
retinoblastomas can block the opening of the Eustachian tube in young children.
a child's immune system is not fully developed.
young children are often in daycare where they easily pick up infections.
eustachian tubes in young children are shorter and more horizontal.