Multiple choice

Cloud Condensation Nuclei (CCN) is an air pollutant. From where is it released?

  1. Metal & chemical industries

  2. Coal mine

  3. Paper mills

  4. Automobile exhaust

  5. Industrial source

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Cloud Condensation Nuclei is a major air pollutant, which is released from paper mills.