Which of the following is a renewable source of energy?

(a) Coal

(b) Petroleum

(c) Solar energy

(d) Natural gas

The correct answer is solar energy. Renewable sources of energy are those that can be replenished naturally in a short period of time and are practically inexhaustible on a human timescale. Solar energy comes directly from the Sun and will continue to be available for billions of years. It does not get depleted when used, unlike coal, petroleum, or natural gas, which are fossil fuels. Fossil fuels take millions of years to form and are consumed much faster than they are created, making them non-renewable.

Solar energy can be harnessed using solar panels, solar heaters, and other technologies to produce electricity and heat. It is considered one of the cleanest sources of energy because it does not release greenhouse gases or pollutants during generation. This makes it environmentally friendly and sustainable for the future. In contrast, burning coal, petroleum, and natural gas not only depletes natural reserves but also causes pollution and contributes to global warming. Therefore, among the given options, solar energy is the renewable source that can meet human needs without harming the planet or running out.