Final answer:
Chief Bromden shows his strength to McMurphy by standing up against Nurse Ratched.
Step-by-step explanation:
Chief Bromden demonstrates his strength to McMurphy in 'One Flew Over the Cuckoo's Nest' by standing up to the oppressive Nurse Ratched.
Despite being portrayed as a mentally ill patient, Chief Bromden reveals his true strength when he finally breaks free from his submissive state and defends McMurphy against the nurse's authority.
For example, in the scene where Chief Bromden smothers McMurphy to ease his suffering, he exhibits immense physical and emotional strength, as it required him to overcome his fears and challenge the oppressive system in the mental institution.