Phrasal verb bring up

Test No. [color=blue]incompl/elem-17 “White Water Rafting”, question 10

All right you win. I promise I won’t bring it again. Why don’t just we go white water rafting instead?

(a) on
(b) up
(c) in

Test No. [color=blue]incompl/elem-17 “White Water Rafting”, answer 10

All right you win. I promise I won’t bring it up again. Why don’t just we go white water rafting instead?

Correct answer: (b) up
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Hi again,
Would you please explain me the meaning of “to bring somthing up”?
Thank you.

Bring up here means talk about/mention/start talking about something.