It’s B why do I have to write 20 characters
Convection is cool things sinking and hot things rising. So for example when you have the heat on the upstairs is always hotter than downstairs because heat rises and continues to go in circles until the whole house it heated up.
arachnoid
a fine, delicate membrane, the middle one of the three membranes or meninges that surround the brain and spinal cord, situated between the dura mater and the pia mater.
If I remember that abiotic means not living then rocks, soil, air.
Community, habitat is in general and ecosystem is the whole place, not just the soil.
