DW Question & Answer Pro is an all-time favourite question & answer plugin for WordPress. Your WordPress site will have a full-featured question & answer section like StackOverflow, Quora or Yahoo Answers.

Demo
https://codecanyon.net/item/dw-question-answer-pro-wordpress-plugin/15057949

Download
https://www.filecad.com/e744/DW-Question-&-Answer-Pro-v1.2.1---WordPress-Plugin.rar