Rahul Aryan

Zen Projects and Rahul have agreed to team up to bring substantial resources into the development of AnsPress and its related themes and extensions, read the full announcement here: https://anspress.net/blog/anspress-update-annoucement/
AnsPress is an open source, developer friendly, question and answer plugin for WordPress. AnsPress adds a full question and answer system to your existing WordPress site. It can be used to create a Q&A network similar to StackOverflow and Quora, or be a single page on existing site. The plugin supports multiple languages, shortcodes, reCAPTCHA, email and push notifications, and more.
AnsPress is not just limited to questions and answers. It can be used in many different ways, like a bug tracker, an internal Q&A board, support ticket forum, FAQ, and more. Anspress is trusted and used by many popular companies and sites at scale.
Performance and Optimizations:
In our latest release, we’ve made big improvements to performance and have tested the plugin in many different server environments. It has run smoothly on every type of server with minimal impact on load times. AnsPress (including all of its functionalities) is very fast compared to other Q&A plugins. In the latest release we have made major improvements to reduce MySQL queries and to increase the page load speed for all page templates within the plugin.
Developer Friendly:
AnsPress is built with developers in mind and can easily be extended to fit your needs. All parts of the template layouts can be overridden. Our source code follows WP coding standards and is properly commented. We are working on a documentation site which will be available soon.
Contributors:
This plugin wouldn’t be possible without the huge amount of contributions we have received. Check our contributors at https://anspress.net/contributors/
Support and Demo:
We provide support on our site: https://anspress.net/questions 
Our support section uses the actual version of AnsPress, so you can check out the support site if you want to see full working version. 
You can also take the demo site for a test drive at https://anspress.net/demo/
AnsPress Key Features:
<ul>
<li>Submit / Filter / Order / Edit / Delete Question</li>
<li>Answer / Comment</li>
<li>Vote and Select Best Answer</li>
<li>Notification Emails and Web Push Notifications</li>
<li>10+ languages supported</li>
<li>Captcha supported</li>
<li>Shortcodes available</li>
<li>Private/Public for Question and Answer</li>
<li>Ability to Follow Questions / Answers</li>
<li>Featured (Sticky) Question</li>
<li>Closed questions</li>
<li>Flag/report questions and answers to moderator</li>
<li>Basic user profile</li>
<li>BuddyPress integration</li>
<li>More to come…</li>
</ul>
Free Add-ons:
<ul>
<li>Reputations</li>
<li>Tags</li>
<li>Categories</li>
<li>Bad words filter</li>
<li>Email notifications</li>
<li>reCaptcha</li>
<li>Dynamic text avatar</li>
</ul>
AnsPress is frequently updated and more features are added based on feedback from our users. This means you are welcome to give us feedback and suggestions as to what you would like to see or need in the plugin. Visit our Github project https://github.com/anspress/anspress or visit our community https://anspress.net/questions/ to get updates and leave feedback.
Page Shortcodes
Use this shortcode in the base page of AnsPress to work properly 
 [anspress]

AnsPress – Question and answer

A free question and answer plugin for WordPress. Made with developers in mind, and highly customizable.

andreuka

WP Q&A Quiz is a easy to use plugin that extend your site with Questions & Answers quiz functionality.
Main Features:
<ul>
<li>Refresh page after user answer question (you can set number of questions in admin)</li>
<li>Set start image for every quiz</li>
<li>Unlimited Quiz</li>
<li>Unlimited Quiz questions/answers</li>
<li>Facebook Share button</li>
<li>Responsive design</li>
<li>Result message settings (set result text & image based on user quiz result)</li>
<li>Easy to use & manage</li>
</ul>
Please use support forums if you have found any bug or have any other problem with plugin

WP Q&A Quiz

Easy to use plugin that extend your site with Questions & Answers quiz functionality.

AnsPress – Question and answer vs WP Q&A Quiz