How to stop posting spam

Question

I had asked user registration spam and this was resolved, but there is still posting spam on site. 
I did Google for this issue and checked reCAPTCHA section on Posting Admin but there is no option to stop such posting spam.

Could you please resolve this issue. 

Thanks in advance.

Comments

To clarify, you have set up reCAPTCHA already?

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Yes, already. Please check second attached SS. I already put secret and site key in the reCaptcha options and saved it.

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recaptcha is working on your site, see http://gateoverflow.net/feedback

Do u still see SPAM. if yes then enable manual verification of user accounts.

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Its not about user registration spam but its about posting spam. User registrations are controlled. Are bots posting there? Are people posting manually?