Final answer:
Hamlet suggests that a defect in character can cause a tragic downfall, reflecting the classical concept of hamartia or tragic flaw.
Step-by-step explanation:
According to Hamlet in Shakespeare's play, a single defect in character can cause a tragic downfall. This notion aligns with Aristotle's concept of hamartia, the tragic flaw. The idea is that while a person can possess many commendable qualities, one significant flaw can lead to their ruin. This is evident in tragedies such as Hamlet and Oedipus, where the protagonists are of noble birth and fall to disastrous ends not due to inherent wickedness but because of a critical error or frailty. Hence, from Hamlet's perspective, the correct option is (c) Cause a tragic downfall.