Which of the following statements is the most accurate? a. energy transfers are never 100% efficient. b. energy transfer is completely efficient. c. energy cannot be transferred to other forms. d. energy transfers can be used to create perpetual-motion machines.

A.Energy transfers are never 100% efficient

Explanation:

According to the  first law of thermodynamics energy can neither be created nor destroyed but it can be converted from one form to another. According to the second law of thermodynamics transfer of energy is never 100% efficient in a machine. There is always loss of energy due to wear and tear of the machinery.

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.