<span>D is the correct answer. Coral reefs need sunlight to grow, so they grow best in shallow water (up to 50m deep) as this means sunlight can reach them. They require salt water to grow and warm temperatures of 20 - 32 degrees Celsius.</span>
For the second one it’s B or C, I dunno if phototropism is a real word cuz all the rest are vital.
1 is moving or kinetic energy of course because it is energy in motion.
it's very practical, because it's on base 10, so conversion between stuff like meters to kilometer is always just a multiplication with 10 to some power
like 1 km = 1000m (10³m)
or 1 m = 10^-3km = 0.001km
same reason for other SI units.
except time, that's base 60, or 12, or 24. that's more complicated, but there isn't any real competition