Identify $B$ from the given diagram showing different biomes based on mean annual temperature and mean annual precipitation.

The photic or euphotic zone extends to what depth from the upper surface of the sea?

Which of the following factors cannot be regarded as belonging to a non-living environment?

$........$ is the most ecologically relevant environmental factor affecting the life of organisms.

Halophytes are

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.