When an organism moves away temporarily from a stressful habitat to a more hospitable area and returns when the stressful period is over,what is this process called?

$I.$ Many xerophytic plants have thick cuticle on leaf epidermis and sunken stomata.
$II.$ Some xerophytic plants have a special photosynthetic pathway $(CAM)$ that enables their stomata to close during the day.
$III.$ $Opuntia$ has spines (modified leaves) and a photosynthetic phylloclade (stem).
$IV.$ All adaptations are genetically fixed in all organisms.
Choose the combination of correct statements.

In desert grasslands,which type of animals are relatively more abundant?

Which one of the following pairs is mismatched?

Rhododendron is the characteristic vegetation of

Warm-blooded animals like mammals from colder climates generally have shorter ears and limbs. This is an explanation of: