Noun, する verb, and の adjective
へんしゅう
どうしてブログ記事を編集するのに一時間もかかったんですか。
Why did it take you an hour to edit a blog article?
Knit and gather everything back together, which you knit. When you do this to fix things and bring it back together, this is an edit.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.