A professor putting 16 poker cards on the table, as follows: Spirit: a 7 Q Red Heart: 3 4 7 9 J Q Plum: 2 3 5 QK square: A 5 Professor selected a piece. Telling this number of this card with his student "A" and told the color "B". Then the professor asked "Jia" and said: "Do you know that the card?" A: "I can't sure it is the card." B: "You know you will say this." A: "Now I know." "B:" Now I know. "Professor is happy to nod. A and B will have a strong logical reasoning ability, and all said honest. According to the above information, tell me what brand is this?
(Please have interested friends only answer, don't analyze)
