The correct answer is: A. about the same.
Transformers and electric motors are both electrical machines that convert energy from one form to another. Transformers convert electrical energy from one voltage to another, while electric motors convert electrical energy into mechanical energy.
The efficiency of a machine is the ratio of the output power to the input power. In other words, it is the percentage of the input power that is converted into useful output power.
The efficiency of transformers is typically very high, typically around 98%. The efficiency of electric motors is also typically very high, typically around 95%.
Therefore, the efficiencies of transformers and electric motors are about the same.
Option B is incorrect because the efficiency of transformers is not much smaller than the efficiency of electric motors.
Option C is incorrect because the efficiency of transformers is not much higher than the efficiency of electric motors.
Option D is incorrect because the efficiency of transformers is not somewhat smaller than the efficiency of electric motors.