The discussion technique that Jennifer uses most clearly in this conversation is, challenging assumptions.
When we want to give a discussion a different approach, we use this technique through What if... questions, it is necessary to present another alternative to respond to things that we already established.
The other techniques are very different from this one, promoting participation would be mostly used by a moderator not a regular participant in the conversation, MAking an objective is to land the discussion into something real, and Asking for rhetorical questions does expect any kind of answer which we do have in here, therefore the other three options are incorrect.
Hello, I could probably answer it more surely if the question was provided in its original format. But for how it was presented, I believe the answer would be C. A callout.
A callout (or call-out) in publishing is a short excerpt within a bigger text, somehow highlighted to call the reader's attention out to that part, specially. It can be a short string of text with its words connected by lines, dots, arrows, or similar, a sentence in bold separated from the text, or written in a different format, usually in a larger font. - This one is very common in magazines and newspapers. (and I believe this is the type that was presented on this excerpt original format).
Fete is the correct answer to this
The answer for your question is B: Formal
