Answer:
I suppose the answer is d)
I know that bats identify the position of object by means of echolocation, so I guess it is connected with irritability
Biosphere, Ecosystem, Communities, Populations, Organisms, Organ systems, Organs, Tissues, Cells, Organelle.
C
Because your DNA is made of nitrogen bases
Adenine
Guanine
Cytosine
Thymine
If the pressure is rising, the density will increase.