Final answer:
The sentence with an ambiguous adverb is 'Brandon fell off the cliff almost a height of 15 feet,' which should be revised for clarity.
Step-by-step explanation:
The sentence with a misplaced or ambiguous adverb is: 'Brandon fell off the cliff almost a height of 15 feet.' The placement of the adverb 'almost' in the sentence suggests that Brandon nearly fell off the cliff, rather than falling off the cliff and almost falling a specific distance. To correct the ambiguity and make the meaning clear, the sentence could be rephrased to: 'Brandon fell off the cliff, falling a height of almost 15 feet.' This clarifies that the 'almost' is modifying the height of the fall rather than the act of falling itself.