29. A certain substance, X, has a triple-point temperature of 20℃ at a pressure of 2.0 atm. Whichone of the following statements cannot possibly be true?
(A) X can exist as a liquid above 20℃
(B) both liquid and solid X have the same vapor pressure at20℃
(C) liquid X can exist as a stable phase at 25℃ , 1 atm
(D) X can exist as a solid above 20℃
(E) allof these statements could be true