AdSense Code error

I am trying to connect my newly created blog to AdSense and it was asked me to add AdSense code to my settings.
As editing in ‘Theme Editor’ is much technical I decided to use a plugging ‘WP QUADS’ to add my code. But when I paste the code, an error message appears and I cannot proceed.
The message is: Can not parse AdSense Code, is the Code valid?
What should I do?
Can someone assist me, please?

The page I need help with: [log in to see the link]