Which Statement Below Is Incorrect

Which statement below is incorrect?

A) Dalton's statement "All atoms of a given element are identical" is no longer accepted because of the existence of isotopes and ions.
B) O₃ (ozone) is considered a molecule but is not considered an element.
C) One mole of aluminum is equal to the number of aluminum atoms in 26.98 g of aluminum.
D) Gases behave the most ideally at high temperatures and low pressures.
E) At least two of the above statements (a-d) are incorrect.