Requirements that the cookware manufacturing company is looking for :
a metal that needs least amount of energy to be raised to high temperatures. (Given)
We are provided with the following options :
1. Aluminium pans are most energy efficient cookwares.
2. Copper pans are the most energy-efficient cookware, but they cost the most.
3. Iron pans require less energy to heat up than copper frying pans, but they cost less.
4. Copper requires the most energy to heat up.
We see that, copper requires less energy to heat up . So, option 4 is ruled out.
Also, iron pans take up less heat than copper, but not the best. So, option 3 is ruled out.
And, Aluminium is energy efficient but not as good as copper.
Hence the company will claim, "Copper pans are the most energy efficient cookwares, but they cost the most. "