The nurse is teaching nursing students about normal physiologic changes in the respiratory system of toddlers. Which best describes why toddlers have fewer respiratory tract infections as they grow older?

A) The amount of lymphoid tissue decreases.
B) Repeated exposure to organisms causes increased immunity.
C) Viral organisms are less prevalent in the population.
D) Secondary infections rarely occur after viral illnesses.

Respiratory Tract Infections

Infections that affect the parts of the body involved in breathing, such as the lungs, throat, and nasal passages.

Lymphoid Tissue

A type of tissue found in the lymphatic system that helps the body fight infection and disease.

Increased Immunity

Increased immunity refers to an enhanced ability of the body to fight off infectious agents and diseases, often achieved through vaccination or natural infection.