how did you react to elizabeth proctor's arrest at the end of this act?

It's all very sad. By the time Elizabeth is incarcerated (around act 4) the hysteria is ridiculous, even for Salem. The accusations of witchcraft have turned into a Puritan free for all. Elizabeth is one of the most honest characters in the play. She is in fact so brutally sincere that saving her husband's "good name" is the only lie that she utters and it pains her to do so. Elizabeth is still graceful under pressure and she does not fly into hysteria of pointing fingers or sharing the blame. For me, Elizabeth's arrest is the beginning of the end to this whole sordid trial. Abigail has unleashed her venom and an innocent lady, already hurt by her husband’s infidelity, is going to be sacrificed for nothing.