To Surrender
する verb
降参 is "surrender" so the verb version would be to surrender.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own. The reading is the same as 降参 as well, of course.
降参しようと思ったことは今まで一度もないんですか。
Haven’t you ever thought about surrendering, even once?