The attribution tag of blogger,i.e the 'POWERED BY BLOGGER', is by default unremovable from blogs.
You might consider leaving it,but if you want to remove it,there's an easy way to do just that.
It was not stated in the BLOGGER TOS that removing this attribute is against the rules.So,you don't have to be trepidated that you might get penalized for this.

To remove the attribute from your blog

All you have to do is follow the following steps=>
  • Go to Design >> Edit HTML.
  • Remember to Backup your template in case something goes wrong.
  • Check the box next to

    Expand Widget.
  • Now,search for ATTRIBUTION1 by pressing CTRL+F on your keyboard.
The code will be displayed like this~
<b:widget id='Attribution1' locked='true' title='' type='Attribution'/>
Just replace TRUE with FALSE and save your Template.Finally,to delete this tag Go to Design >> Page element and click on "Attribution" & select REMOVE.

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