Hello. Could you help me choose the correct answer?
- Much (that - which) your father has said shows that he is angry.
This sentence sounds odd, but I'd go with 'that'. 'That' is common after 'much'. I see that the author here wants to use 'much' as a pronoun. It means 'much (information / of the information)'. I think what is more natural to say is:
- Much of what your father has said shows that he is angry.