The answer is B: Less than a decade ago, the HSUS...an affiliate [Human Society International].
Brackets are used to give the writers (when they need to add information) an opportunity to add an explanation, or emphasis to a word, or change a <em>quote to fit to a sentence, but without changing the meaning of the text</em>. In A) <em>global work</em> doesn't need explanation; C) <em>decade</em> doesn't need explanation; D) <em>HSUS</em> was already explained in the first sentence of the text.
Try to underline the particular word so that it would be much easier
Answer:
Dear (Names)
I'm very sorry for how I treated you.
I'm trying my hardest to be a good friend but sometimes it just doesn't work out as I planned.
I've been struggling with this whole pandemic, and I just can't deal with my head anymore.
I really love you guys as my friends and I want it to be a happy friendship again!
I am so sorry about treating you guys badly.
I hope you can forgive me.
Sincerely (Your name)
Explanation:
The correct answer is the fourth option. The other three are grammatically incorrect.