Final answer:
To contradict a previous statement about the instrument John Bonham played, the word 'drums' in the sentence would be stressed.
Step-by-step explanation:
To contradict a previous statement that said John Bonham played the guitar, you would stress the word drums in the sentence "John Bonham played the drums." This emphasis contradicts the earlier statement by making it clear that the instrument played was not the guitar, but the drums. In spoken English, vocal emphasis on specific words can change the meaning or implication of a sentence and thus is important for clarity, especially in situations where something is being corrected or contradicted.