I interpret (D) as "It is impossible to say that any previous statement is true", as opposed to "The previous statements are not true".
I would (now) also say (D).
]]>If it was the second case then you could immediately tell it was false without reading the question, because one of x<y, x=y and x>y will always be true, regardless of what x and y are.
The correct answer is (D) by that interpretation, because as Daniel has shown, it's possible for (A) or (B) to be true (and so we don't know which is).
]]>(a) x<y ( B) x> y (C)x=y (D)noon of these
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