Only to use nitrates when heart pain is active and progressing. Afterwards, see your heart specilist..
The answer is A. i say this because when they use sunlight as energy, cabon dioxide and water are converted into organic material, they are used as cellular functions ( such as biosynthesis and respiration ). An able autotroph is able to make his own food.
They had to adapt to the heat and to learn to survive long periods without water
