Inside the chloroplast (a membrane-bound organelle present in plant cells)
Water is a key element and necessary thing life needs in order to live and thrive without water everything would die.
The correct answer is a law
Laws explain what occurs, not why it occurs. This is a law because it states that a limp stalk of celery will become crisp if put into ice water. There is no explanation why or how it occurs, only that it will happen.