Usually enzyme inhibitors slow down the enzymes activity, so in this case, I would put D.
No, no look my shoes its gucci xd
A. An increase in the amount of acid rain can change the pH of soil in an ecosystem.
What is the second question? If it is in a picture I cannot see it, just comment the question below and I'll see if I can help you :3
Answer A seems like the best choice for this question. Just think about some of the synonyms for therefore—”hence,” “consequently,” and “thus.” Because the adverb therefore often plays the role of a conjunction, it's sometimes called a conjunctive adverb.
B isn’t the correct answer to this question because you use “On the other hand” to introduce two contrasting points, facts, or ways of looking at something.
C isn’t the correct answer because we are not comparing or contrasting anything in this sentence.
D isn’t the correct answer because “Especially” is used in a formal sentence example: She can't be sure she will win, especially at this early stage of the campaign.