The sentence that contains a misplaced modifier is the second option.
"Amber awed the judges tumbling on the mat."
The word "tumbling" is a misplaced modifier since in that place of the sentence it is modifying the word judges instead of modifying "Amber."
A misplaced modifier is a word, phrase, or clause that is improperly separated from the word it modifies. As a result of the separation, sentences with this mitake often sound awkward, ridiculous, or confusing.
