Which Substance Is Likely to Be a Cause of Respiratory

question 61

Multiple Choice

Which substance is likely to be a cause of respiratory illnesses in developing countries? 

• A) asbestos 
• B) particulate matter 
• C) formaldehyde 
• D) cigarette smoke

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Definitions:

Noun Clause

A dependent clause that functions as a noun within a larger sentence, often starting with words like "that," "whom," or "where."

Restrictive

Pertains to a limiting or controlling condition or rule.

Nonrestrictive

Descriptive text that provides additional information but is not essential to the meaning of the sentence.

Carbonic Acid

A weak, unstable acid (H2CO3) formed in solution when carbon dioxide dissolves in water and participates in the carbonate buffer system in blood.