[单项选择]A father asks his son "How many letters are there in the Alphabet (字母表)”“I don’t know," says his son. His father says," You don’t know You are in school for many years and you don’t know how many letters are there in the Alphabet" He is very angry. His son says, "No. But let me ask you a question, Dad. You often go to the post office, please tell me how many letters are there in the post office/ The son is good at English. [A] True. [B] False.