The conclusion drawn above depends on which of the following assumptions? A. Extinct languages do not offer up words that capture concepts and emotional states in ways that fundamentally differ from those of existing languages. B. Many languages have words that virtually overlap in the meaning they convey. C. Each year hundreds of the world's languages go extinct, once there are no longer any native speakers remaining. D. It is possible for one person to learn all of the world's existing languages. E. The range of concepts and emotional states is the only indication of a language's thoroughness.