How did slaves who were still on plantations during the civil war the union cause? a) they poisoned horses that might be used in war b) they did things to sabotage production on the slaveholders' plantations c) they pretended they were too ill to support the slaveholders d) they sent spy reports to the north on what they overheard

I believe the most reasonable answer would be D. This is because if for B, they sabotaged the production, then they would be punished. Or for A, if they poisoned the horses they would be killed. Or for C, if they pretended to be ill, well everyone can't be ill so the plantation owner would know something wasn't right. And if they just overheard things well, that's not their fault and they could easily pass the information onto others.

Hope this helps!
Good day to you.