Complete the correct pronoun: “Is _____ book John’s?” “Yes, _____ is.”

Complete the correct pronoun:

“Is _____ book John’s?” “Yes, _____ is.” — Is this book John’s?” “Yes, it is.” This book is John's. 

“Is that book John’s?” “Yes, it is.” That book is John's.

“Are these books John’s?” “Yes, they are.” These books are John's.

“Are those books John’s?” “Yes, they are." Those books are John's.