Question

energy efficiency
when energy is put into a system, some of that energy is lost as what?
energy is never lost
heat, sound, and light

Explanation:

In energy transfer within a system, according to physical principles (like the second law of thermodynamics), when energy is input into a system, some energy is dissipated (lost) in forms like heat, sound, or light (due to inefficiencies, friction, etc.). The option "energy is never lost" refers to conservation of energy (it's transformed, not lost), but the question asks what it's lost as (the form of dissipation), so "heat, sound, and light" is correct.

Answer:

heat, sound, and light