Whenever energy changes form, people sometimes say that some energy is "lost." What is meant by this?
A. The energy is not truly lost; it transforms into forms that are not easily put to use.
B. The process of changing form reduces the total amount of energy in the universe.
C. Whenever energy changes form in one location, a corresponding change in the opposite direction must take place somewhere else.
D. Sometimes a "mistake" or an inefficiency in the transformation causes energy to be destroyed.

A. The energy is not truly lost: it transforms into forms that are not easily put to use.

Explanation:

This is due to the fact that when we use energy, it seems to have disappear, but it really hasn't. In fact, when we use energy, it is changing into another form that has to be converted in order for energy to be present once again.

this allows people to make the best decision or pursue the best option. when alternatives are weighed using their advantages and disadvantages, the option whose disadvantages outweigh the advantages (based on a qualitative or quantitative analysis) are shunned while those whose advantages outweigh their disadvantages are pursued.  

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