Four cards lie on a table. Each card has a number printed on one side and a colour on the other. The faces visible on the cards are $2,3,$ red, and blue. Proposition: If a card has an even value on one side. then its opposite face is red. The cards which MUST be turned over to verify the above proposition are
(A) 2, red
(B) 2. 3. red
(C) 2 . blue
(D) 2 , red, blue
Four cards lie on a table. Each card has a number printed on one side and a colour on the other. The faces visible on the cards are $2,3,$ red, and blue. Proposition: If a card has an even value on one side. then its opposite face is red. The cards which MUST be turned over to verify the above proposition are
(A) 2, red
(B) 2. 3. red
(C) 2 . blue
(D) 2 , red, blue