Multiple choice

Which of the following is an unwanted change in the environment caused by harmful substances?

  1. biodiversity

  2. overpopulation

  3. pollution

  4. evolution

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

Pollution is defined as the presence or introduction into the environment of a substance or thing that has harmful or poisonous effects. It is an unwanted change caused by human or natural activity.