Answer: A) Sulphur dioxide Explanation: Air pollutants are solid particles, gases, and liquid droplets in the air that can adversely affect ecosystems and the health of humans.   Major ambient air pollutants include toxic metals, polycyclic aromatic hydrocarbons, benzene, particulate matter (PM), nitrogen oxides, sulfur oxides, carbon monoxide, and ozone. Power plants, factories, and vehicle and air traffic are the most important anthropogenic sources of air pollution.   In addition, natural sources such as wildfires and volcanic activity contribute to ambient air pollution.

Most building codes require ceiling fans to be mounted on special fan-rated boxes made of metal or strong plastic with deep-threaded holes for the mounting screws. The box must be mounted firmly by attaching it directly to a framing member or using a fan-rated brace.

1. The first vitamin discovered in 1897 was thiamine, also known as vitamin B1.

2. Thiamine was discovered by Dutch physician Christiaan Eijkman.

3. Vitamin B1 helps body cells convert carbohydrates into energy and maintain proper functioning of the heart, muscles and digestive system.