Abundance. Hope this helps :))
There are two things that occur in aquarium ammonia chemisty. 1. the build up of natural ammonia and nitrate in the water. 2. displacement of oxygen in the water caused by the ammonia. This is a very real threat especially when you have a new tank that is still cycling or when the biological filter has been upset or removed.
Look for these main symptoms if you suspect ammonia poisoning in your fish tank:
-loss of appetite
-lethargic fish
-fish gasping for air/breath at the top of the water
-fish laying at the bottom of the tank
-red/purple gills
-red streaking on the fish's body
- fins becoming torn and jagged
-scales on fish falling off or turning black
answer:
by having a high genetic level of melanin in your skin, you're skin is more protected from the ultra violet sun rays. Darker skinned races have more melanin present, these races originate from hot countries where sunlight is often present; the production of melanin in their skin allows them to reflect and inhibits they're skin from becoming extremely damaged. Light skinned races don't have a large amount of melanin due to they're native countries lacking sunlight. This is an evolutionary adaptation of the human race.
...........The answer is A