Which of the following characteristics primarily defines a ‘renewable’ energy source?

💡 Explanation:

A renewable energy source is fundamentally defined by its ability to replenish itself naturally over a relatively short human timescale, ensuring its long-term availability. Options A and D are not universally true (e.g., renewable energy can be used for heating, and some forms like biomass or the manufacturing of infrastructure can have emissions). Option B describes non-renewable energy.