Answer:
I think that the answer would be D
Answer:
The observable traits expressed by an organism are referred to
EXPLANATION:
An organism's underlying genetic makeup, consisting of both physically visible and non-expressed alleles, is called its genotype. Mendel's hybridization experiments demonstrate the difference between phenotype and genotype.
I believe it is organ level
Your answer should be lakes and forests. Acid precipitation will rot out forests because of the acid content and in lakes it raises the PH balance making it more acidic which in turn makes it harder for anything to live in these lakes or drink from them. (Hope this helps ^-^)