In the oceans,the environment is perpetually dark at depths of:

Life does not exist on the moon due to the absence of .......

What is the basis of variations in the physical and chemical conditions of different habitats?

Why are stenohaline organisms unable to survive in marine habitats for a long period?

Given below are five statements.
$A.$ Organisms living in oceans,lakes,and rivers also face water-related problems.
$B.$ Euryhaline can tolerate a wide range of salinities.
$C.$ Stenohaline are restricted to a narrow range of salinities.
$D.$ Many freshwater animals cannot live for long in sea water because of the osmotic problems they would face.
$E.$ The salt concentration (measured as salinity in parts per thousand) is less than $5$ in inland waters,$30-35$ in the sea,and $>100$ in some hypersaline lagoons.

Which ecological factors are the most strong determinants of various biomes?