The answer is it improved the economy.
explanation: the second and third option are the basically the same just reworded which eliminates those two. if you search that question online, it most of the headings of the articles talk about growth. growth = improvement. leaving the first option as your answer
The density of air ρ (Greek: rho) (air density) is the mass<span> per unit volume of Earth's atmosphere. Air density, like air pressure, decreases with increasing altitude. It also changes with variation in temperature and humidity.</span>
Yemen was known as the happy land