HOW TO ADD CAPTCHA TO BLOGGER.COM BLOGS TO MINIMIZE COMMENT SPAM?

To start, log in to your blogger.com account and click on the "Settings" tab. You'll see a top nav menu like this:

Click on the "Comments" sub-menu and you'll see a pile of different options, with the one you want about 2/3 of the way down the screen:
Select "Yes" here, choose "Save Settings", and you'll now have word capture enabled on your comments and that should, almost like magic, either eliminate your comment spam completely or at least reduce it to an easily manageable trickle of annoyance rather than a tsunami of pain.
Here's how it'll end up looking once you have everything configured:
By the way, if you hear people talk about captcha or comment captcha this is what they're talking about, even if the Blogger folk (who are, of course, owned by Google) refer to it in their interface as "word verification".