Is this your book?

Yes, it's ________．

[　　]

Is this your book?

Yes, it's ________．

[　　]

--Is this your book?

-- ________．It's her book．

A．It's a book．                                            B．No，it isn't．

C．Yes，it is．                                        D．This is my book．

—Is this          book?　—Yes，it’s          English book．

A．a；a          B．a；an          C．art；an