Which of the following are the $Key$ elements that cause variation in the physical and chemical conditions of an ecosystem?

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

Why do high altitude areas have brighter sunlight and lower temperatures compared to the plains?

Match the types of animals in Column-$I$ with their adaptations in Column-$II$:

Column-$I$	Column-$II$
$i$. Eurythermal	$a$. Can tolerate only a narrow range of salinity
$ii$. Stenothermal	$b$. Can tolerate a wide range of temperature
$iii$. Euryhaline	$c$. Can tolerate a wide range of salinity
$iv$. Stenohaline	$d$. Can tolerate only a narrow range of temperature

The figure depicts annual variations in temperature and precipitation for different biomes. Based on the provided graph,identify the correct sequence of biomes corresponding to the labels $A, B, C, D, E, F$ as shown in the standard $NCERT$ diagram:
$1$. Temperate forest
$2$. Tropical forest
$3$. Coniferous forest
$4$. Grassland
$5$. Desert
$6$. Arctic and Alpine tundra

Select the incorrect statement from the following.