Which best describes energy? a. once energy is used, all living organisms must make more. b. energy can only change forms. c. energy can only be transferred. d. energy can change forms and be transferred.

Option D, Energy can change forms and be transferred.

Explanation:

As per law of conservation of Energy,  Energy is neither created nor destroyed. However, it can only be transformed from one form to another. Also energy can be transferred from one substance  to another.

For example -

In the process of photosynthesis, energy of sun is transferred to green plants and trees which later convert the radiant energy of sun into chemical energy.

Hence, option D is true.

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.

answer; three;