I think it would be more logical to use the past tense i.e. those books were written by this woman. The action of writing has past but the meeting or introduction of the person is happening now.
I don't understand the difference between "Those" and "These" .... Sometimes "đó" is accepted, sometimes it isn't.
Đó is those and these is này.
How can the answer previously be marked as wrong, then that answer be used as the question with the same translation on the next page?