Answer:
Below.
Explanation:
Air pollutants.
Allergies.
Chronic sinusitis.
Lack of pertussis immunization.
Malnutrition (particularly in children)
Exposure to chemicals, fumes, and dust.
Smoke inhalation.
I feel like Becky should pay attention to the ingredients. Also she should pay attention to which one fits her needs, but I feel like ingredients is very important.
