How can a speaker show a compare contrast relationship between ideas?

A) Identify a problem in present ideas on how to solve it
B) An idea occurred and what results had
C) Discuss the similarities and difference between ideas
D) Organize ideas in the order they happened

C) Discuss the similarities and difference between ideas

By discussing the similarities and differences between ideas, a speaker can effectively show a compare contrast relationship. This can be done by highlighting key points of each idea and then directly comparing them to show how they relate or differ from each other. This approach helps the audience understand the relationship between the ideas and the nuances of each.