If you want to add Google's reCaptcha (https://www.google.com/recaptcha/intro/index.html) to your Drupal 7 forms programmatically you need to follow these two steps:

1) Install and enable captcha (https://www.drupal.org/project/captcha) and recaptcha (https://www.drupal.org/project/recaptcha) modules. The best ...

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