We can learn about the living conditions of a vanished culture by examining its language. Thus, it is likely that the people who spoke Proto-Indo-European, the language from which all Indo-European languages descended, lived in a cold climate, isolated from ocean or sea, because Proto-Indo-European lacks a word for "sea," yet contains words for "winter," "snow," and "wolf."

Which one of the following, if true, most seriously weakens the argument?

(A) A word meaning "fish" was used by the people who spoke Proto-Indo-European.
(B) Some languages lack words for prominent elements of the environments of their speakers.
(C) There are no known languages today that lack a word for "sea."
(D) Proto-Indo-European possesses words for "heat."
(E) The people who spoke Proto-Indo-European were nomadic.