The same problem as here, but for 6.x:#332550: Can´t translate "This question is for testing whether you are a human visitor and to prevent automated spam submissions."
What's the reason of translating it on settings page? If for that reason is locale?
Yep, translating it on the settings page is pretty ad-hoc.
Duplicate of #834042: use i18n module for translating of CAPTCHA description
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