Which factor is most important in predisposing toddlers to frequent infections?

A) Respirations are abdominal.
B) Pulse and respiratory rates are slower than those in infancy.
C) Defense mechanisms are less efficient than those during infancy.
D) Toddlers have a short, straight internal ear canal and large lymph tissue.

Toddlers continue to have the short, straight internal ear canal of infants. The lymphoid tissue of the tonsils and adenoids continues to be relatively large. These two anatomic conditions combine to predispose the toddler to frequent infections. The abdominal respirations and lowered pulse and respiratory rate of toddlers do not affect their susceptibility to infection. The defense mechanisms are more efficient compared with those of infancy.