What could be the 'tragic flaw' in Hamlet?

The correct answer is 'None of these'.

Key Points

Tragic flaw refers to a trait in a character leading to his downfall, and the character is often the hero of the literary piece.

• Shakespeare's tragic hero Hamlet's fatal flaw is his failure to act immediately to kill Claudius, his uncle, and the murderer of his father.
• His tragic flaw is 'procrastination'.
• His continuous awareness and doubt delay him in performing the needed. 
• Hamlet finally kills Claudius but only after realizing that he is poisoned.
• His procrastination, his tragic flaw, leads him to his doom along with that of the other characters he targets.
• But Hamlet is not responsible for the events which complicate the plot.
• Fate, chance, and the supernatural also play a critical role in Hamlet. 

From the above, we can conclude that Hamlet was neither Noble nor Oedipus Complex nor Vaulting ambition.