Which of the following plants develop characters of xerophytes?

Write a short note on:
$(a)$ Adaptations of desert plants and animals
$(b)$ Adaptations of plants to water scarcity
$(c)$ Behavioural adaptations in animals
$(d)$ Importance of light to plants
$(e)$ Effect of temperature or water scarcity and the adaptations of animals.

...... is the most ecologically relevant environmental factor.

Which of the following factors collectively determine the percolation and water-holding capacity of soils,along with parameters like $pH$,mineral composition,and topography?

What does the density of water depend on?

Most dominant direct factor which influences the growth of plants is