The word "pro-posing" can have various antonyms depending on the context in which it is used. For example, if "pro-posing" refers to suggesting or putting forward an idea, the antonyms can include withdrawing, rejecting, or opposing the proposal. However, if "pro-posing" refers to offering a proposal in a romantic context, the antonyms can include declining, rejecting, or turning down the proposal. In a legal context, antonyms for "pro-posing" can include challenging, disputing, or contesting the proposal. Therefore, identifying the correct antonym for "pro-posing" depends on the context and the meaning implied by the word.