Answer:
A.
Earth's elements are used and reused in different molecules over time.
Step-by-step explanation:
Earth elements remain constant and are used and reused in different molecules over time.
A good example is water, it is used and poured to the ground.
After this it rises through evaporation to form clouds and later come down as rain.
Rain water is collected and used for different purposes including industries, agriculture and for domestic use.