user: You are a structured reasoning expert tasked with solving problems step by step. 
You first think about the reasoning process in the mind and then provide the answer. The reasoning process and answer should be enclosed within <think> </think> and <answer> </answer> tags, respectively, i.e., <think> reasoning process here </think> <answer> answer here </answer>. 
Given a question and the associated knowledge graph triplets (entity, relation, entity), you are asked to answer the question with these triplets and your own knowledge. 
You can break down the original question into several sub-questions and explore the given knowledge graph to solve them step-by-step. If there are multiple possible answers, choose one as the final answer. 
After thinking, when you finally reach a conclusion, clearly state the answer within <answer> </answer> tags, i.e., <answer> answer here </answer>. 
Question: What did the actor that was the character, Rachel Zachary, die of? 
Knowledge Triplets: Cancer, medicine.disease.includes_diseases, Appendix cancer
Topic, freebase.type_profile.published, Published
Audrey Hepburn, people.deceased_person.cause_of_death, Appendix cancer
Film character, freebase.type_profile.kind, Portrayal
Film character, common.topic.article, m.02_96_z
Film character, freebase.type_profile.strict_included_types, Fictional Character
Topic, freebase.type_profile.kind, Portrayal
Film character, freebase.type_profile.strict_included_types, Topic
Film character, type.type.properties, Portrayed in films (dubbed)
Film, type.domain.types, Film character
Audrey Hepburn, film.actor.film, m.02vbmn7
Appendix cancer, medicine.disease.parent_disease, Cancer
Appendix cancer, people.cause_of_death.people, Joan Stein
Oncology, medicine.medical_specialty.diseases_treated, Appendix cancer
Appendix cancer, medicine.disease.medical_specialties, Oncology
Film character, type.type.expected_by, Character
Rachel Zachary, film.film_character.portrayed_in_films, m.02vbmn7
Character, rdf-schema#range, Film character
Appendix cancer, people.cause_of_death.people, Judy Rodgers
m.02vbmn7, film.performance.film, The Unforgiven
m.02vbmn7, film.performance.actor, Audrey Hepburn
Film character, type.type.properties, Portrayed in films
Cancer, people.cause_of_death.includes_causes_of_death, Appendix cancer
Tim Breslin, people.deceased_person.cause_of_death, Appendix cancer
Character, owl#inverseOf, Portrayed in films
Appendix cancer, base.consumermedical.medical_term.consumer_name, Appendix cancer
Film character, type.type.expected_by, Other conquests
Film character, freebase.type_profile.published, Published
Film character, type.type.domain, Film
Judy Rodgers, people.deceased_person.cause_of_death, Appendix cancer
Fictional Character, freebase.type_profile.kind, Portrayal
Appendix cancer, people.cause_of_death.people, Audrey Hepburn
Audrey Hepburn, people.deceased_person.cause_of_death, Appendix cancer
Film character, type.type.expected_by, Character using Wham-O product
Film character, freebase.type_hints.included_types, Fictional Character
Rachel Zachary, film.film_character.portrayed_in_films, m.02vbmn7
Fictional Character, freebase.type_profile.published, Published
Film character, type.type.expected_by, Killed by
m.02vbmn7, film.performance.actor, Audrey Hepburn
Rachel Zachary, common.topic.notable_for, g.12h312mh9
Fictional Character, freebase.type_hints.included_types, Topic
Joan Stein, people.deceased_person.cause_of_death, Appendix cancer
Appendix cancer, people.cause_of_death.people, Tim Breslin
m.02vbmn7, film.performance.character, Rachel Zachary
Character, type.property.reverse_property, Portrayed in films
Film character, freebase.type_hints.included_types, Topic
Appendix cancer, base.schemastaging.context_name.pronunciation, g.125_ls7md
Rachel Zachary, common.topic.notable_types, Film character
The Unforgiven, film.film.starring, m.02vbmn7
Character, type.property.expected_type, Film character
Appendix cancer, people.cause_of_death.parent_cause_of_death, Cancer
Fictional Character, freebase.type_profile.strict_included_types, Topic
Film character, freebase.type_profile.kind, Annotation

Answer: Appendix cancer