We've been asked for a counter to the argument, so we need a statement that makes the conclusion invalid. In this case, the conclusion is that "Our words are meaningless and cannot be distinguished from their opposites". The rationale given here is that its impossible to make a clear distinction between "bald" and "having hair", which are opposites.

A - This is irrelevant. In English at least, the conclusion remains unaffected. OUT

B - If a word can have multiple meanings, it still can suggest that there is little difference between a word and its opposite. OUT

C - This is very similar to B. One word being applied to multiple situations and meanings. OUT

D - This suggests that the problem the author mentioned was not one of meaninglessness, but one of precision. It certainly adds up that "having hair" is imprecise about how much hair, and at what degree one is considered bald. By providing an alternative explanation, it weakens the argument that words are meaningless. CORRECT

E - This is not relevant to the argument. We are not told enough about the link between thinking and meaning. OUT