Wheezing’ is the most relevant Health Effect in case of the air pollutant.  

Explalnation:

As per WHO Air pollution is the contamination of the indoor or outdoor environment by any chemical, physical or biological agent that modifies the natural characteristics of the atmosphere.
Sulfur dioxide:

• It affects the respiratory system, particularly lung function, and can irritate the eyes.
• Sulfur dioxide irritates the respiratory tract and increases the risk of tract infections.
• It causes coughing, Wheezing mucus secretion, and aggravates conditions such as asthma wheezing, and chronic bronchitis.​

Nitrogen dioxide:

•  NO₂ primarily gets in the air from the burning of fuel. NO₂ forms from emissions from cars, trucks and buses, power plants, and off-road equipment
• Breathing air with a high concentration of NO₂ can irritate airways in the human respiratory system.

Carbon monoxide :

• It is harmful because it binds to hemoglobin in the blood, reducing the ability of blood to carry oxygen.
• This interferes with oxygen delivery to the body's organs.
• The most common effects of CO exposure are fatigue, headaches, confusion, and dizziness due to inadequate oxygen delivery to the brain.

Ozone:

• Breathing ground-level ozone can trigger a variety of health problems including chest pain, coughing, throat irritation, and congestion.
• It can worsen bronchitis, emphysema, and asthma.
•  Ozone also can reduce lung function and inflame the lining of the lungs. Repeated exposure may permanently scar lung tissue.

Hence we can say that sulfur dioxide Is the most relevant air pollutant which causes wheezing.