The correct option is A.
Adam Smith was a great philosopher and a key member of Scottish enlightenment. He believed in free market economy and is known as the modern father of capitalism. Capitalism is an economic and political system, in which the means of production are based on private ownership.
This is a type of precipitation that comes from fronts encasing tropical cyclones, which forms when warm air meets cold air.
Protozoa are single celled organisms. They come in many different shapes and sizes ranging from an Amoeba which can change its shape to Paramecium with its fixed shape and complex structure. They live in a wide variety of moist habitats including fresh water, marine environments and the soil.