Why do you think that economics is often said to be the science that studies choices?

Economics is driven by individual choices, especially in capitalist systems: The effect of demand and supply is driven by what people choose to spend their money on, and how they value certain things over others.

For example, if people choose to go to Egypt and not to Tunisia for holidays, this will influence the economies of those two countries differently!

The best sociological research method would have to be using experiments although it has some disadvantages as well

Carbon monoxide is usually more dangerous indoors.