The amount of methane in biogas is approximately:

Explanation

Biogas is predominantly composed of methane (CH4) and carbon dioxide (CO2). The methane content typically ranges from 50% to 75% by volume. Option C accurately reflects this range. Option A suggests a much lower methane content than is typical, Option B overestimates the possible upper limit, and Option D does not encompass the full typical range, omitting the lower end.