<span>Water is vital to the existence of plant life. Not only do plants use it to keep their cells from drying out, but they need water to move nutrients and raw materials throughout their systems to areas where photosynthesis and seed production take place. When water stress occurs, whether caused by drought or root impairment, many invisible processes are affected.</span>
Answer: Gold.
Explanation: Water, CO2, and table salt are compounds. They are composed of two or more separate elements; a mixture, where as gold is neither.
