The correct answer is A. Price floor.
A price floor is a government-mandated minimum price for a good or service. The minimum wage is a price floor on labor. It is a law that sets a minimum wage that employers must pay their employees. The minimum wage is intended to protect workers from being paid too little, but it can also have negative consequences, such as reducing employment.
A price ceiling is a government-mandated maximum price for a good or service. The price ceiling is intended to protect consumers from being charged too much, but it can also have negative consequences, such as creating shortages.
The equilibrium wage is the wage that would be paid in a free market, without government intervention. The equilibrium wage is determined by the supply and demand for labor.
Efficiency of labor is a measure of how well workers are able to produce goods and services. Efficiency of labor can be increased by improving technology, training workers, and providing better working conditions.
I hope this helps!