Question

Which of the following is not one of the causes of river pollution?

• A. Dumping of garbage
• B. Aquatic organisms and algae
• C. Discharge of untreated sewage
• D. Discharge of industrial effluents

Answer 1

The correct option is B Aquatic organisms and algae

Aquatic organisms and algae does not cause river pollution.

Autotrophs are organisms that can make their own food. A plant is a familiar example of an autotroph. Plants produce their own food through the process of photosynthesis. Photosynthesis converts light energy into chemical energy and food. Photosynthetic autotrophs are also called photo-autotrophs. This term distinguishes them from chemo-autotrophs, which are capable of converting carbon dioxide into chemical energy and food without light energy.