问题
                    
‘I’____the first letter in the word‘irregular’,and there is___‘u’and ___‘l’in it.
                            A:is, a, an
B:am, an, a
C:is, an, a
D:am, a, an
                        
                        B:am, an, a
C:is, an, a
D:am, a, an
正确答案是: