Microbial fuel cells are considered a source of substainable energy. why?1. They use living organisms as catalysts to generate electricity from certain susbtracts. 2. They use a variety of inorganic materials as susbtrates.3. They can be installed in waste water treatment plants to cleanse water and produce electrucity.which statements given above is / are correct?

• A. 1 only
• B. 2 and 3 only
• C. 1 and 3 only
• D. 1, 2 and 3