The Grinch, the Cat in Hat, and the Once-ler are explaining how many Truffula trees the Once-ler has killed. If only one of the three is truthful, is it possible to find out how many Truffula trees the Once-ler actually destroyed? If not, narrow the answer as much as possible with the given information. Describe fully.
The Once-ler: I've destroyed more than one million Truffula trees.
The Grinch: It's less than one million.
The Cat in the Hat: It's at least one.