I would recommend Norton Internet Security 2013.One of the best antivirus software available in the market.

Avast forever. It is a smart virus guard for me. Because it can give 100% safe to my PC.

I will recommend Norton antivirus. This is 2013’s best viruses guard.

Kaspersky because it's never let my pc speed down.

Avast is best PC antivirus guard because I have been using my PC from a long time so far nothing has happened.

My choice is Nod32. I've been using it for the long time and satisfied with its performance.

I have a very good relationship with Avast :)

I don't know what's the best paid antivirus, but for free, I guest avast is the best antivirus. I use it for long years and didn't get any problems

Honestly, I did not expect that a Baidu antivirus is an excellent and free professional antivirus and ultra fast cloud security software.

Windows Defender is also a good option and comes pre-installed in latest editions of Windows OS.