The word that should not be used in the comparative or superlative degree is D. absolute. The word absolute is already at the highest degree possible - nothing can be more or less absolute than something else, because it is already complete and perfect. You cannot say - It is the most absolute of all - because that would mean all things are absolute, which obviously is not true. Wealthy, smart, and sweet do have comparative and superlative degrees, but absolute doesn't.
