Multiple choice

Biogas is mainly

  1. oxygen

  2. hydrogen

  3. methane

  4. nitrogen

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

Biogas is a renewable energy source produced when organic matter breaks down in the absence of oxygen. It is composed primarily of methane (around 50-70%), along with carbon dioxide and small amounts of other gases. Methane is the combustible component.