If two engines are given the same amount of fuel, the more efficient engine can do more work than the less efficient engine can.
The following questions could be asked to help make scientific or technological progress. Which of the following questions is best
asked and answered as part of a scientific investigation, not as part of technological improvements?

A. How can efficient engines be built more cheaply?

B. How efficient can an engine be, in theory?

C. How can a more efficient engine be built?

D. How can the efficiency of an existing engine be improved?

As the two engines are of the same amount of fuel consumption and more efficient the engine gets more efficient out can do more work and thus scientist think of the question as to how or which part of the technological progress can be made so as to develop a much faster and better technology that is economical and reliable.