<u>Answer</u> <span>d. renewable energy </span> <u>Explanation</u> Energy can be said to be one of the most basic commodity in the 21st century. Every household uses energy in almost all its doing eg. cooking lighting, cleaning, entertainment such televisions and radios, communication etc. For this reason, the scientist have to find the most sustainable source of energy. Some are not sustainable as they can be used up and other pollute the environment. By the year 2030, the most expected source of energy to have the highest rate of consumption is renewable energy.