The correct option is C.
Specie specific signals are those signals which are limited to only one specie of animal. The specie usually use it to communicate with the members of the specie. Each signal normally have a specific meaning and will produce uniform response in its receivers.
Answer:
A. Fast growing crops, heavy rains
Explanation:
Fast growing crops will increase soil nitrates, while heavy rains will decrease soil nitrates.
I'd say it should be D. Peat. Hope this helps! =^-^=
It's the pull of gravity on an object.
Hope this helps!