Doubt in text completion

I tried applying the math strategy but it didn’t quite work, and I had to look at the answer choices. How would you all do it?

surprisingly usually indicates a contrast:

(brief) surprisingly (lengthy)

Indeed (supports the idea)
So, yeah, its lengthy survey seems extra

Well I knew surprisingly is a contrast but is the opposite lengthy?

I meant the opposite of brief

brief = short

opposite of brief = long or in details

brief (surprisingly) ______
brief (surprisingly) NOT brief

Oh okay, makes sense, so that should be comprehensive. Any idea about the other blank?

After the first sentence, there is a supporting word “indeed.”

Indeed is used to emphasize a statement confirming something already suggested

The survey is comprehensive. Indeed, it is_________.

Guess a blank that would support the idea that the survey is lengthy, or comprehensive. Redundant makes sense because, it means extra and that supports the stated idea that the survey is not brief.

The survey is comprehensive. Indeed, it is redundant.

Got it, thanks.