how does cystic fibrosis increase the risk of respiratory infections such as bronchitis and pneumonia?

a.by causing mucus to build up in airways.

b.by destroying cells of the immune system.

c.by reducing blood flow to the lungs.

d.by increasing air flow to the lungs.

Respuesta :

Answer:

CFTR controls the flow of water and salt in and out of the body's cells. Changes cause mucus to become thickened and sticky. This first affects the small airways in the lungs. Over time, it can affect all airways.

Explanation:

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