Joanna: The only way for a company to be successful, after emerging from bankruptcy, is to produce the same goods or services that it did before going bankrupt  It is futile for such a company to try to learn a whole new business  Ruth: Wrong  The Kelton Company was a major mining operation that went into bankruptcy
On emerging from bankruptcy, Kelton turned its mines into landfills and is presently a highly successful waste-management concern
She establishes a conclusion by excluding the only plausible alternative to that conclusion.