Sunlight is the direct source of energy for a(n)autotrophheterotrophboth a and bnone of the above

The answer would be the first one: autotroph. Autotrophs are organisms that produce their own food, right? So just think about plants. In order for plants to go through photosynthesis and produce their own food, they need to take energy directly from the sun, along with water and carbon dioxide of course. Heterotrophs, on the other hand, cannot produce their own food and rely on other organisms (humans, for example). Hope this helped :)

Because some people pollute water ans waste it