Concept:A relative pronoun must fit the noun it refers to and its job in the clause. For a person who is the subject of the verb, we use
who.
Explanation:The clause after "aunt" is "____ spoke to us". The missing word is the subject of the verb "spoke", because the aunt did the speaking.
So a subject relative pronoun for a person is needed:
who.
"His aunt who spoke to us lives in Tamale."
whom is the object form, so it cannot be the subject of "spoke".
which is used for animals and things, not people.
whose shows possession ("whose son spoke to us"), and no possessed noun follows here.
Key point: The printed option A was
that. "His aunt that spoke to us" is also accepted in standard English, so two options were right. Option A has been changed to
whose so that only one answer fits.
Answer:Option C (who)