Let \( R \) and \( S \) be two relations on a set \( A \). Then, which one of the following is n...

Let \( R \) and \( S \) be two relations on a set \( A \). Then, which one of the following is not true?
(A) \( R \) and \( S \) are transitive, then \( R \cup S \) is also transitive
(B) \( R \) and \( S \) are transitive, then \( R \cap S \) is also transitive
(C) \( R \) and \( S \) are reflexive, then \( R \cap S \) is also reflexive
(D) \( R \) and \( S \) are symmetric, then \( R \cup S \) is also symmetric