Purines are adenine and guanine. So the answer should be D (Pyrimidines). besides, phosphate group and pentose sugar are a part of a nucleotide.
Answer:
The trees' growth might be affected
Explanation:
A pH above 7 indicates that the soil is no more acidic and that it had turned basic or alkaline in nature. This may affect the functioning of enzymes as this value is very far from optimum pH value. Thus growth is affected.
The formula SF_2 expresses one-third the amount of F.
The F:S ratio in the first compound is 6:1.
We want a compound with one third the amount of F, so F:S = 2:1.
The simplest formula with this ratio is SF_2.